LMB Limbach Holdings Inc

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Basis of Presentation

References in these financial statements to the Company refer collectively to the accounts of Limbach Holdings, Inc. and its wholly-owned subsidiaries, including LHLLC, Limbach Facility Services LLC (“LFS”), Limbach Company LLC (“LC LLC”), Limbach Company LP, Harper Limbach LLC, Harper Limbach Construction LLC, Limbach Facility & Project Solutions LLC, Jake Marshall, LLC (“JMLLC”), Coating Solutions, LLC (“CSLLC”) and ACME Industrial Piping, LLC (“ACME”) for all periods presented, unless otherwise indicated. All intercompany balances and transactions have been eliminated.

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the requirements of Form 10-Q and Rule 8-03 of Regulation S-X for smaller reporting companies. Consequently, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. Readers of this report should refer to the consolidated financial statements and the notes thereto included in the Company's most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 8, 2023.

Use of Estimates

The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements for assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, the reported amounts of revenue and expenses during the reported period, and the accompanying notes. Management believes that its most significant estimates and assumptions have been based on reasonable and supportable assumptions and the resulting estimates are reasonable for use in the preparation of the condensed consolidated financial statements. The Company’s significant estimates include estimates associated with revenue recognition on construction contracts, costs incurred through each balance sheet date, intangibles, property and equipment, fair value accounting for acquisitions, insurance reserves, fair value of contingent consideration arrangements and contingencies. If the underlying estimates and assumptions upon which the condensed consolidated financial statements are based change in the future, actual amounts may differ from those included in the accompanying condensed consolidated financial statements.

Unaudited Interim Financial Information

The accompanying interim Condensed Consolidated Balance Sheets, Condensed Consolidated Statements of Operations, Condensed Consolidated Statements of Stockholders’ Equity and Condensed Consolidated Statements of Cash Flows for the

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periods presented are unaudited. Also, within the notes to the condensed consolidated financial statements, the Company has included unaudited information for these interim periods. These unaudited interim condensed consolidated financial statements have been prepared in accordance with GAAP. In the Company's opinion, the accompanying unaudited condensed consolidated financial statements contain all normal and recurring adjustments necessary for a fair statement of the Company’s financial position as of September 30, 2023, its results of operations and equity for the three and nine months ended September 30, 2023 and 2022 and its cash flows for the nine months ended September 30, 2023 and 2022. The results for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023.

The Condensed Consolidated Balance Sheet as of December 31, 2022 was derived from the Company's audited financial statements included in its Annual Report on Form 10-K filed with the SEC on March 8, 2023, but is presented as condensed and does not contain all of the footnote disclosures from the annual financial statements.

Recently Adopted Accounting Standards

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments, which introduced an expected credit loss methodology for the measurement and recognition of credit losses on most financial instruments, including trade receivables and off-balance sheet credit exposure. Under this guidance, an entity is required to consider a broader range of information to estimate expected credit losses, which may result in earlier recognition of losses. This ASU also requires disclosure of information regarding how a company developed its allowance, including changes in the factors that influenced management’s estimate of expected credit losses and the reasons for those changes. The Company adopted ASU 2016-13 on January 1, 2023 using the modified retrospective method, whereby the guidance was applied prospectively as of the date of adoption and prior periods are not restated. The adoption of this ASU did not have a material impact on the Company's financial position or results of operations.

The Company assessed the scope of its financial assets and determined that the guidance associated with ASU 2016-13 is relevant to its trade accounts receivable and contract assets, including retainage. The Company’s trade receivables include amounts from work completed in which it has billed or has an unconditional right to bill its customers. The majority of the Company’s trade receivables are contractually due in less than a year. The Company further assessed the guidance based on its segment portfolio of receivables. While the Company’s construction-type GCR and ODR financial assets are often in the same subset of customers and industries, the Company’s construction-type related project work is typically bonded and the customers to which they perform work are well-known, solvent and have no history of material receivable write-offs. On the contrary, the Company’s service-type work, in particular its ODR core service work, is smaller in nature and is usually more susceptible to customer write-offs. As such, there is greater risk of credit loss on the Company’s ODR-related service-type receivables. The Company’s contract assets include amounts due under retainage provisions and costs and estimated earnings in excess of billings on uncompleted contracts. The Company has policies and procedures in place where it reviews claims and change orders on a quarterly basis to determine legal entitlement and recoverability in accordance with ASC Topic 606. As such, the Company has determined the risk of credit loss on its contracts assets to be remote.

The Company develops its allowances for credit losses, which represent an estimate of expected losses over the remaining contractual life of its ODR-related service-type receivables, using an aging method. Under the aging method, the Company assigns its accounts receivable to a level of delinquency and applies a loss rate to each class. Loss rates are determined based on historical loss experiences with customers, the consideration of a customer’s financial condition, current market economic conditions and a forecast of future economic conditions when appropriate. When the Company becomes aware of a customer's inability to meet its financial obligation, a specific reserve is recorded to reduce the receivable to the expected amount to be collected.

As part of the Company’s analysis of expected credit losses, it may analyze receivables with customers on an individual basis in situations where such accounts receivables exhibit unique risk characteristics and are not expected to experience similar losses to the rest of their class.

Recent Accounting Pronouncements

The FASB has issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting in March 2020. This new guidance provides optional expedients for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform, on financial reporting. The risk of termination of the London Interbank Offered Rate (LIBOR), has caused regulators to undertake reference rate reform initiatives to identify alternative reference rates that are more observable or transaction based that are less susceptible to manipulation. ASU 2020-04 was effective between March 12, 2020 and December 31, 2022. However, in December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, extending the sunset date under Topic 848 from December 31, 2022 to December 31, 2024 to align the temporary accounting relief guidance with the expected LIBOR cessation date of June 30, 2023.

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In addition, in January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848): Scope. The amendments in this update refine the scope for certain optional expedients and exceptions for contract modifications and hedge accounting to apply to derivative contracts and certain hedging relationships affected by the discounting transition. As a result of ASU 2022-06, an entity may now elect to apply the amendments in this update from the beginning of an interim period beginning as of March 12, 2020, through December 31, 2024. The Company has evaluated the impact of adopting the reference rate reform guidance (both ASU 2020-04 and ASU 2021-01) on its consolidated financial statements and has determined that these pronouncements did not have a significant impact. As discussed in Note 6, the A&R Credit Agreement removed LIBOR as a benchmark rate and now utilizes SOFR (as defined in the A&R Credit Agreement) as its replacement. During the second quarter of 2023, the Company entered into the Second A&R Credit Agreement (as defined in Note 6), which also utilizes SOFR as a benchmark rate. In addition, the Company’s interest rate swap utilizes SOFR as its benchmark rate.

In August 2020, the FASB issued ASU 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity, which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity and amends the scope guidance for contracts in an entity's own equity. The ASU addresses how convertible instruments are accounted for in the calculation of diluted earnings per share by using the if-converted method. The guidance is effective for all entities for fiscal years beginning after March 31, 2024, albeit early adoption is permitted no earlier than fiscal years beginning after December 15, 2020. Management is currently assessing the impact of this pronouncement on its condensed consolidated financial statements.

ACME Transaction

On July 3, 2023 (the “Effective Date”), the Company, LFS and ACME (the “Acquired Company”), and the owner of the Acquired Company (the “Seller”) entered into a Purchase Agreement (the “Purchase Agreement”) pursuant to which LFS purchased all of the outstanding equity interests in the Acquired Company from the Seller (the “ACME Transaction”). The ACME Transaction closed on the Effective Date. As a result of the ACME Transaction, the Acquired Company became a wholly-owned indirect subsidiary of the Company. ACME specializes in performing industrial maintenance, capital project work, and emergency services for specialty chemical and manufacturing clients, and is a leading mechanical solutions provider for hydroelectric producers. The acquisition expands the Company’s market share within its existing operating footprint, provides further exposure to an attractive customer base and supports the Company's continued ODR growth strategy.

Total consideration paid by the Company for the ACME Transaction at closing was $5.0 million (the “Closing Purchase Price”), consisting of cash paid to the Seller, subject to typical adjustments for working capital. Of the consideration paid to the Seller, approximately $0.4 million is being held in escrow for indemnification purposes. The purchase price is subject to customary post-closing adjustments. In addition, the Seller may receive up to an aggregate of $2.5 million in cash, consisting of two individual tranches of $0.5 million and $2.0 million pursuant to the terms of the Purchase Agreement, if the gross profit of the Acquired Company equals or exceeds (i) $2.0 million in the 12-month period beginning on the Effective Date (the “First ACME Earnout Period”) or (ii) $2.5 million in the 12-month period beginning on the first anniversary of the Effective Date (the “Second ACME Earnout Period” and together with the First ACME Earnout Period, the “ACME Earnout Payments”).

The Company recorded $0.3 million in acquisition-related expenses associated with professional fees related to the ACME Transaction during the three and nine months ending September 30, 2023, which are included in selling, general and administrative expense in the condensed consolidated statement of operations.

Allocation of Purchase Price. The ACME Transaction was accounted for as a business combination using the acquisition method. The following table summarizes the preliminary purchase price and estimated fair values of assets acquired and liabilities assumed as of the Effective Date, with any excess of purchase price over estimated fair value of the identified net assets acquired recorded as goodwill. As a result of the acquisition, the Company recognized $2.3 million of goodwill, all of which was allocated to the ODR segment and fully deductible for tax purposes. Such goodwill primarily related to anticipated future earnings. The following table summarizes the preliminary allocation of the fair value of the assets and liabilities of the ACME Transaction as of the Effective Date by the Company.

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(in thousands)						Purchase Price Allocation
Consideration:
Cash						$	5,181
Earnout provision						1,121
Total Consideration						6,302
Fair value of assets acquired:
Cash and cash equivalents						298
Accounts receivable						1,150
Contract assets						414
Property and equipment						488
Operating lease right-of-use assets						301
Intangible assets						2,300
Amount attributable to assets acquired						4,951
Fair value of liabilities assumed:
Accounts payable, including retainage						170
Current operating lease liabilities						195
Accrued expenses and other current liabilities						138
Contract liabilities						373
Long-term operating lease liabilities						106
Amount attributable to liabilities assumed						982
Goodwill						$	2,333

For working capital items, such as cash and cash equivalents, accounts receivable, other current assets, accounts payable and accrued expenses and other current liabilities, the Acquired Company's carrying value was assumed to represent the fair value of these assets due to the current nature of the assets and liabilities. There was no difference between the contract value and fair value of accounts receivable acquired.

The estimated fair value of property and equipment, generally consisting of vehicles, machinery, and equipment, was estimated using the cost approach. Significant unobservable inputs in the estimate of fair value under this approach included management's assumptions about the replacement costs for similar assets, the relative age of the acquired assets and any potential economic or functional obsolescence associated with the acquired assets. As a result, the estimated fair value of the property and equipment represented a Level 3 fair value measurement.

As part of the purchase price allocation, the Company identified certain definite-lived intangible assets associated with customer relationships with third-party customers and the acquired trade name and trademarks. The fair value of the customer relationships with third-party customers was determined using the multi-period excess earning method under the income approach. The multi-period excess earnings method is a variation of the discounted cash-flow analysis, which isolates the cash flows that can be associated with a single intangible asset and measures fair value by discounting it back to present value. The fair value of the acquired trade name and trademarks intangible asset was determined using an income approach, specifically known as the relief-from-royalty method. This method requires identifying the future revenue that would be generated by the trademark, multiplying it by a royalty rate deemed to be avoided through ownership of the asset and discounting the projected royalty savings amounts back to the acquisition date. The royalty rate used in the valuation was based on a consideration of market rates for similar categories of assets. Some of the more significant estimates and assumptions inherent in determining the fair value of the identifiable intangible assets are associated with forecasting cash flows and profitability, which represent Level 3 inputs.

The Company calculates amortization of the acquired intangible assets using the straight-line method over the estimated useful lives of each acquired intangible assets. Amortization expense recorded in the consolidated statements of operations for the period from the Effective Date to September 30, 2023 was approximately $0.1 million. The estimated annual amortization expense for the remainder of 2023 is approximately $0.1 million, and $0.3 million for each of the next five years.

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Intangible assets, net as of September 30, 2023 are detailed below.

(in thousands)						Gross Carrying Amount						Accumulated Amortization						Net Intangible Assets						Weighted Average Useful Life (Years)
Trade name and trademarks						$	400					$	(18)					$	382					5.5
Customer relationships						1,900						(46)						1,854						10.3
Total						$	2,300					$	(64)					$	2,236					6.3

The aforementioned contingent ACME Earnout Payments are associated with the achievement of specified gross profit milestones. The Company estimated that the fair value of the ACME Earnout Payments was approximately $1.1 million at the date of acquisition, of which the majority of this balance was included in other long-term liabilities in the Company’s consolidated balance sheet as of September 30, 2023. The Company determined the initial fair value of the ACME Earnout Payments based on the Monte Carlo Simulation method, which represented a Level 3 measurement. As of the Effective Date, the ACME Earnout Payments associated with the ACME Transaction were valued utilizing discount rates of 8.65% and 14.49%. The discount rates were calculated using the build-up method with a risk-free rate commensurate with the term of the ACME Earnout Payments based on the U.S. Treasury Constant Maturity Yield and certain metric risk premiums determined with reference to a long-term risk free rate, a weighted average cost of capital and certain adjustments for operational leverage. Subsequent to the Effective Date, the ACME Earnout Payments are re-measured at fair value each reporting period. Changes in the estimated fair value of the contingent payments subsequent to the acquisition date are recognized immediately in earnings.

The Company generates revenue from construction type contracts, primarily consisting of fixed-price contracts, to deliver HVAC, plumbing, and electrical construction services to its customers. The duration of its contracts generally ranges from three months to two years. Revenue from fixed price contracts is recognized on the cost-to-cost method, measured by the relationship of total cost incurred to total estimated contract costs. Revenue from time and materials contracts is recognized as services are performed. The Company believes that its extensive experience in HVAC, plumbing, and electrical projects, and its internal cost review procedures during the bidding process, enable it to reasonably estimate costs and mitigate the risk of cost overruns on fixed price contracts.

The Company generally invoices customers on a monthly basis, based on a schedule of values that breaks down the contract amount into discrete billing items. Costs and estimated earnings in excess of billings on uncompleted contracts are recorded as a contract asset until billable under the contract terms. Billings in excess of costs and estimated earnings on uncompleted contracts are recorded as a contract liability until the related revenue is recognizable. The Company classifies contract assets and liabilities that may be settled beyond one year from the balance sheet date as current, consistent with the length of time of the Company’s project operating cycle.

Contract assets

Contract assets include amounts due under retainage provisions and costs and estimated earnings in excess of billings on uncompleted contracts. The components of the contract asset balances as of the respective dates were as follows:

(in thousands)			September 30, 2023						December 31, 2022						Change
Contract assets
Costs and estimated earnings in excess of billings on uncompleted contracts			$	26,007					$	33,573					$	(7,566)
Retainage receivable			21,846						27,880						(6,034)
Total contract assets			$	47,853					$	61,453					$	(13,600)

Retainage receivable represents amounts invoiced to customers where payments have been partially withheld, typically 10%, pending the completion of certain milestones, satisfaction of other contractual conditions or the completion of the project. Retainage agreements vary from project to project and balances could be outstanding for several months or years depending on a number of circumstances such as contract-specific terms, project performance and other variables that may arise as the Company makes progress towards completion.

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Contract assets represent the excess of contract costs and profits (or contract revenue) over the amount of contract billings to date and are classified as a current asset. Contract assets result when either: (1) the appropriate contract revenue amount has been recognized over time in accordance with ASC Topic 606, but a portion of the revenue recorded cannot be currently billed due to the billing terms defined in the contract, or (2) costs are incurred related to certain claims and unapproved change orders. Claims occur when there is a dispute regarding both a change in the scope of work and the price associated with that change. Unapproved change orders occur when a change in the scope of work results in additional work being performed before the parties have agreed on the corresponding change in the contract price. The Company routinely estimates recovery related to claims and unapproved change orders as a form of variable consideration at the most likely amount it expects to receive and to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. Claims and unapproved change orders are billable upon the agreement and resolution between the contractual parties and after the execution of contractual amendments. Increases in claims and unapproved change orders typically result from costs being incurred against existing or new positions; decreases normally result from resolutions and subsequent billings.

The current estimated net realizable value on such items as recorded in contract assets and contract liabilities in the condensed consolidated balance sheets was $19.7 million and $28.5 million as of September 30, 2023 and December 31, 2022, respectively. The Company currently anticipates that the majority of such amounts will be approved or executed within one year. The resolution of those claims and unapproved change orders that may require litigation or other forms of dispute resolution proceedings may delay the timing of billing beyond one year.

Contract liabilities

Contract liabilities include billings in excess of contract costs and provisions for losses. The components of the contract liability balances as of the respective dates were as follows:

(in thousands)			September 30, 2023						December 31, 2022						Change
Contract liabilities
Billings in excess of costs and estimated earnings on uncompleted contracts			$	46,545					$	43,806					$	2,739
Provisions for losses			147						201						(54)
Total contract liabilities			$	46,692					$	44,007					$	2,685

Billings in excess of costs and estimated earnings on uncompleted contracts represent the excess of contract billings to date over the amount of contract costs and profits (or contract revenue) recognized to date. The balance may fluctuate depending on the timing of contract billings and the recognition of contract revenue.

Provisions for losses are recognized in the condensed consolidated statements of operations at the uncompleted performance obligation level for the amount of total estimated losses in the period that evidence indicates that the estimated total cost of a performance obligation exceeds its estimated total revenue.

The net (overbilling) underbilling position for contracts in process consisted of the following:

(in thousands)			September 30, 2023						December 31, 2022
Revenue earned on uncompleted contracts			$	625,765					$	678,014
Less: Billings to date			(646,303)						(688,247)
Net (overbilling) underbilling			$	(20,538)					$	(10,233)
(in thousands)			September 30, 2023						December 31, 2022
Costs in excess of billings and estimated earnings on uncompleted contracts			$	26,007					$	33,573
Billings in excess of costs and estimated earnings on uncompleted contracts			(46,545)						(43,806)
Net (overbilling) underbilling			$	(20,538)					$	(10,233)

Revisions in Contract Estimates

The Company recorded revisions in its contract estimates for certain GCR and ODR projects. During the three months ended September 30, 2023, the Company recorded material gross profit write-ups on three GCR projects for a total of $3.1 million, inclusive of a $1.2 million write-up related to the settlement of a past claim, and one material GCR project gross profit write-down for $0.7 million and one material ODR project gross profit write-down for $0.6 million. During the nine months ended

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September 30, 2023, the Company recorded material gross profit write-ups on two GCR projects for a total of $2.2 million, inclusive of a $1.2 million write-up related to the settlement of a past claim, and one material GCR project gross profit write-down for $0.5 million and one material ODR project gross profit write-down for $0.7 million. During the three months ended September 30, 2022, the Company did not record any material gross profit write-ups or write-downs that had a net gross profit impact of $0.5 million or more. During the nine months ended September 30, 2022, the Company recorded material gross profit write-ups on two GCR projects for a total of $2.0 million and two material GCR project gross profit write-downs for a total of $1.1 million.

Remaining Performance Obligations

Remaining performance obligations represent the transaction price of firm orders for which work has not been performed and exclude unexercised contract options. The Company’s remaining performance obligations include projects that have a written award, a letter of intent, a notice to proceed or an agreed upon work order to perform work on mutually accepted terms and conditions.

As of September 30, 2023, the aggregate amount of the transaction prices allocated to the remaining performance obligations of the Company's GCR and ODR segment contracts were $227.0 million and $138.1 million, respectively. The Company currently estimates that 27% and 48% of its GCR and ODR remaining performance obligations as of September 30, 2023, respectively, will be recognized as revenue during the remainder of 2023, with the substantial majority of remaining performance obligations to be recognized within 24 months, although the timing of the Company's performance is not always under its control.

Additionally, the difference between remaining performance obligations and backlog is due to the exclusion of a portion of the Company’s ODR agreements under certain contract types from the Company’s remaining performance obligations as these contracts can be canceled for convenience at any time by the Company or the customer without considerable cost incurred by the customer.

Goodwill

Goodwill was $13.7 million and $11.4 million as of September 30, 2023 and December 31, 2022, respectively, and is entirely associated with the Company's ODR segment. The Company tests its goodwill and indefinite-lived intangible assets allocated to its reporting units for impairment annually on October 1, or more frequently if events or circumstances indicate that it is more likely than not that the fair value of its reporting units and indefinite-lived intangible assets are less than their carrying amount. The Company has the option to assess goodwill for possible impairment by performing a qualitative analysis to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. A quantitative assessment is performed if the qualitative assessments results in a more-likely-than-not determination or if a qualitative assessment is not performed.

The Company did not recognize any impairment charges on its goodwill or intangible assets during the three and nine months ended September 30, 2023 and September 30, 2022.

The following table summarizes the carrying amount and changes in goodwill associated with the Company's segments for the nine months ended September 30, 2022 and for the year ended December 31, 2022.

(in thousands)			GCR						ODR						Total
Goodwill as of January 1, 2022			$	—					$	11,370					$	11,370
Goodwill as of December 31, 2022			—						11,370						11,370
Goodwill associated with the ACME Transaction			—						2,333						2,333
Goodwill as of September 30, 2023			$	—					$	13,703					$	13,703

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Intangible Assets

Intangible assets are comprised of the following:     

(in thousands)			Gross carrying amount						Accumulated amortization						Net intangible assets, excluding goodwill
September 30, 2023
Amortized intangible assets:
Customer relationships – GCR – Jake Marshall			$	570					$	(148)					$	422
Customer relationships – ODR – Jake Marshall			3,050						(737)						2,313
Customer relationships – ODR – ACME			1,900						(46)						1,854
Customer relationships – ODR – Limbach			4,710						(3,944)						766
Favorable leasehold interests – Limbach			190						(109)						81
Backlog – GCR – Jake Marshall			260						(260)						—
Backlog – ODR – Jake Marshall			680						(680)						—
Trade name – Jake Marshall			1,150						(342)						808
Trade name – ACME			400						(18)						382
Total amortized intangible assets			12,910						(6,284)						6,626
Unamortized intangible assets:
Trade name – Limbach(1)			9,960						—						9,960
Total unamortized intangible assets			9,960						—						9,960
Total amortized and unamortized assets, excluding goodwill			$	22,870					$	(6,284)					$	16,586

(1)    The Company has determined that its trade name has an indefinite useful life. The Limbach trade name has been in existence since the Company’s founding in 1901 and therefore is an established brand within the industry.

(in thousands)			Gross carrying amount						Accumulated amortization						Net intangible assets, excluding goodwill
December 31, 2022
Amortized intangible assets:
Customer relationships – GCR – Jake Marshall			$	570					$	(87)					$	483
Customer relationships – ODR – Jake Marshall			3,050						(436)						2,614
Customer relationships – ODR – Limbach			4,710						(3,765)						945
Favorable leasehold interests – Limbach			190						(97)						93
Backlog – GCR – Jake Marshall			260						(178)						82
Backlog – ODR – Jake Marshall			680						(465)						215
Trade name – Jake Marshall			1,150						(202)						948
Total amortized intangible assets			10,610						(5,230)						5,380
Unamortized intangible assets:
Trade name – Limbach			9,960						—						9,960
Total unamortized intangible assets			9,960						—						9,960
Total amortized and unamortized assets, excluding goodwill			$	20,570					$	(5,230)					$	15,340

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Long-term debt consists of the following obligations as of:

(in thousands)			September 30, 2023						December 31, 2022
A&R Wintrust Term Loan - term loan payable in quarterly installments of principal, plus interest through February 2026			—						21,453
Wintrust Revolving Loans			10,000						—
Finance leases – collateralized by vehicles, payable in monthly installments of principal, plus interest ranging from 3.96% to 8.60% through 2027			6,949						4,954
Financing liability			5,351						5,351
Total debt			22,300						31,758
Less - Current portion of long-term debt			(2,472)						(9,564)
Less - Unamortized discount and debt issuance costs			(391)						(666)
Long-term debt			$	19,437					$	21,528

Wintrust Term and Revolving Loans

On February 24, 2021, LFS, LHLLC and the direct and indirect subsidiaries of LFS from time to time included as parties to the agreement (the “Wintrust Guarantors”) entered into a credit agreement (the “Wintrust Credit Agreement”) by and among LFS, LHLLC, Wintrust Guarantors, the lenders party thereto from time to time, Wheaton Bank & Trust Company, N.A., a subsidiary of Wintrust Financial Corporation (collectively, “Wintrust”), as administrative agent and L/C issuer, Bank of the West as documentation agent, M&T Bank as syndication agent, and Wintrust as lead arranger and sole book runner.

In accordance with the terms of the Wintrust Credit Agreement, Lenders provided to LFS (i) a $30.0 million senior secured term loan (the “Wintrust Term Loan”); and (ii) a $25.0 million senior secured revolving credit facility with a $5.0 million sublimit for the issuance of letters of credit (the “Wintrust Revolving Loan” and, together with the Wintrust Term Loan, the “Wintrust Loans”). Proceeds of the Wintrust Loans were used to refinance certain existing indebtedness, finance working capital and other general corporate purposes and fund certain fees and expenses associated with the closing of the Wintrust Loans.

The Wintrust Revolving Loan initially bore interest, at LFS’s option, at either LIBOR (with a 0.25% floor) plus 3.5% or a base rate (with a 3.0% floor) plus 0.50%, subject to a 50 basis point step-down based on the ratio between the senior debt of the Company and its subsidiaries to the EBITDA (earnings before interest, income taxes, depreciation and amortization) of LFS and its subsidiaries for the most recently ended four fiscal quarters. The Wintrust Term Loan initially bore interest, at LFS’s option, at either LIBOR (with a 0.25% floor) plus 4.0% or a base rate (with a 3.0% floor) plus 1.00%, subject to a 50 (for LIBOR) or 75 (for base rate) basis point step-down based on the Senior Leverage Ratio (as defined below).

LFS was initially required to make principal payments on the Wintrust Term Loan in $0.5 million installments on the last business day of each month commencing on March 31, 2021 with a final payment of all principal and interest not sooner paid on the Wintrust Term Loan due and payable on February 24, 2026.

In conjunction with the Company's acquisitions of JMLLC and CSLLC (the “Jake Marshall Transaction”), the Company entered into an amendment to the Wintrust Credit Agreement (the “A&R Wintrust Credit Agreement”). In accordance with the terms of the A&R Credit Agreement, Lenders provided to LFS (i) a $35.5 million senior secured term loan (the “A&R Wintrust Term Loan”); and (ii) a $25 million senior secured revolving credit facility with a $5 million sublimit for the issuance of letters of credit (the “A&R Wintrust Revolving Loan” and, together with the Term Loan, the “A&R Wintrust Loans”). The overall Wintrust Term Loan commitment under the A&R Wintrust Credit Agreement was recast at $35.5 million in connection with the A&R Credit Agreement. A portion of the A&R Wintrust Term Loan commitment was used to fund the closing purchase price of the Jake Marshall Transaction. The A&R Credit Agreement was also amended to: (i) permit the Company to undertake the Jake Marshall Transaction, (ii) make certain adjustments to the covenants under the A&R Credit Agreement (which were largely done to make certain adjustments for the Jake Marshall Transaction), (iii) allow for the Earnout Payments (as defined in Note 8) under the Jake Marshall Transaction, and (iv) make other corresponding changes to the A&R Credit Agreement.

The A&R Wintrust Revolving Loan bore interest, at LFS’s option, at either the Term SOFR (as defined in the A&R Credit Agreement) (with a 0.15% floor) plus 3.60%, 3.76% or 3.92% for a tenor of one month, three months or six months, respectively, or a base rate (as set forth in the A&R Credit Agreement) (with a 3.0% floor) plus 0.50%, subject to a 50 basis point step-down based on the ratio between the senior debt of the Company and its subsidiaries to the EBITDA of LFS and its subsidiaries for the most recently ended four fiscal quarters (the “Senior Leverage Ratio”). The A&R Wintrust Term Loan bore

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interest, at LFS’s option, at either Term SOFR (with a 0.15% floor) plus 4.10%, 4.26% or 4.42% for a tenor of one month, three months or six months, respectively, or a base rate (with a 3.0% floor) plus 1.00%, subject to a 50 (for Term SOFR) or 75 (for base rate) basis point step-down based on the Senior Leverage Ratio.

The A&R Wintrust Term Loan was payable through a combination of (i) monthly installments of approximately $0.6 million due on the last business day of each month commencing on December 31, 2021, (ii) annual Excess Cash Flow payments as defined in the A&R Wintrust Credit Agreement, which are due 120 days after the last day of the Company's fiscal year and (iii) Net Claim Proceeds from Legacy Claims as defined in the A&R Wintrust Credit Agreement. Subject to defaults and remedies under the A&R Credit Agreement, the final payment of all principal and interest not sooner paid on the A&R Wintrust Term Loan was due and payable on February 24, 2026. Subject to defaults and remedies under the A&R Credit Agreement, the A&R Wintrust Revolving Loan would have matured and become due and payable by LFS on February 24, 2026. During the second quarter of 2022, the Company made certain Excess Cash Flow and Net Claim Proceeds payments of $3.3 million and $2.1 million, respectively, which concurrently reduced the outstanding A&R Wintrust Term Loan balance. In addition, during the third quarter of 2022, the Company made a Net Claim Proceeds payment of $0.6 million, which was also applied against the outstanding A&R Wintrust Term Loan balance.

The A&R Wintrust Loans were secured by (i) a valid, perfected and enforceable lien of the administrative agent on the ownership interests held by each of LFS and Wintrust Guarantors in their respective subsidiaries; and (ii) a valid, perfected and enforceable lien of the administrative agent on each of LFS and Wintrust Guarantors’ personal property, fixtures and real estate, subject to certain exceptions and limitations. Additionally, the re-payment of the A&R Wintrust Loans shall be jointly and severally guaranteed by each Wintrust Guarantor.

The A&R Credit Agreement contained representations and warranties, covenants and events of default that are customary for facilities of this type, as more particularly described in the A&R Credit Agreement. The A&R Wintrust Loans also contain three financial maintenance covenants, including (i) a requirement to have as of the last day of each quarter for the senior leverage ratio of the Company and its subsidiaries not to exceed an amount beginning at 2.00 to 1.00, (ii) a fixed charge coverage ratio of not less than 1.20 to 1.00 as of the last day of each fiscal quarter, commencing with the fiscal quarter ending December 31, 2021, and (iii) no unfinanced capital expenditures, except for unfinanced capital expenditures in the ordinary course of business not exceeding in the aggregate $4.0 million during any fiscal year; and no default or event of default (as defined by the agreement) has occurred and is continuing, 50% of any portion of this annual limit, if not expended in the fiscal year for which it is permitted, may be carried over for expenditure in the next following fiscal year as stipulated by the agreement. LFS and its affiliates maintain various commercial and service relationships with certain members of the syndicate and their affiliates in the ordinary course of business.

On May 5, 2022, the Company, LFS and LHLLC entered into a first amendment and waiver to the A&R Wintrust Credit Agreement (the “First Amendment to the A&R Wintrust Credit Agreement”) with the lenders party thereto and Wintrust, as administrative agent. The First Amendment to the A&R Wintrust Credit Agreement modifies certain definitions within the A&R Wintrust Credit Agreement, and make other corresponding changes, including: (i) the definition of “EBITDA” to allow for the recognition of certain restructuring charges and lease breakage costs not previously specified, (ii) the definition of “Excess Cash Flow” to exclude the aggregate amount of the Earnout Payments paid in cash, (iii) the definition of “Total Funded Debt” to exclude certain capitalized lease obligations for real estate based on the approval of each lender and (iv) the definition of “Disposition” to include a clause for the sale and leaseback of certain real property based on the approval of each lender.

In July 2022, the Company entered into an interest rate swap agreement to manage the risk associated with a portion of its variable-rate long-term debt. The interest rate swap involves the exchange of fixed-rate and variable-rate payments without the exchange of the underlying notional amount on which the interest payments are calculated. The new swap agreement became effective on July 14, 2022 and will terminate on July 31, 2027. The notional amount of the swap agreement is $10.0 million with a fixed interest rate of 3.12%. If the one-month SOFR (as defined in the A&R Credit Agreement) is above the fixed rate, the counterparty pays the Company, and if the one-month SOFR is less than the fixed rate, the Company pays the counterparty, the difference between the fixed rate of 3.12% and one-month SOFR. The Company has not designated this instrument as a hedge for accounting purposes. As a result, the change in fair value of the derivative instrument is recognized directly in earnings on the Company's condensed consolidated statements of operations as a gain or loss on interest rate swap. Refer to Note 8 for further information regarding this interest rate swap.

On September 28, 2022, the Company, LFS and LHLLC entered into a second amendment and waiver to the amended and restated Wintrust credit agreement (the “Second Amendment to the A&R Wintrust Credit Agreement”) with the lenders party thereto and Wintrust, as administrative agent. The Second Amendment to the A&R Wintrust Credit Agreement incorporates certain restricted payment provisions, among other things, to permit LFS to repurchase shares under the Company’s Share Repurchase Program (as defined in Note 7).

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On May 5, 2023, LFS, LHLLC and the direct and indirect subsidiaries of LFS from time to time included as parties to the agreement entered into the Second Amended and Restated Credit Agreement (the “Second A&R Credit Agreement”) with the lenders party thereto and Wintrust, as administrative agent, which amends and restates the A&R Wintrust Credit Agreement. In accordance with the Second A&R Credit Agreement (i) lenders provided to LFS a $50.0 million senior secured revolving credit facility with a $5.0 million sublimit for the issuance of letters of credit, an increase of $25.0 million over the A&R Wintrust Revolving Loan, with a maturity date of February 24, 2028 (the “Second A&R Wintrust Revolving Loan”), and (ii) LFS repaid the then outstanding principal balance of the A&R Wintrust Term Loan using proceeds of the Second A&R Wintrust Revolving Loan. Prior to the execution of this agreement, the Company repaid $9.6 million of the then outstanding balance under the A&R Term Loan with cash on hand. As a result of the early repayment of the A&R Wintrust Term Loan and certain changes to the members of the loan syndicate under the Second A&R Wintrust Credit Agreement, the Company wrote off approximately $0.3 million of unamortized debt issuance costs, which are reported as a loss on early debt extinguishment on the Company's condensed consolidated statements of operations.

Prior to its repayment on May 5, 2023 and as of September 30, 2022, the interest rate in effect on the non-hedged portion of the A&R Wintrust Term Loan was 9.25% and 7.25%, respectively. For the period from January 1, 2023 through May 5, 2023, the Company incurred interest on the A&R Wintrust Term Loan at a weighted average annual interest rate of 8.76%. For the three and nine months ended September 30, 2022, the Company incurred interest on the A&R Wintrust Term Loan at a weighted average annual interest rate of 6.35% and 5.08%, respectively.

The Second A&R Wintrust Revolving Loan bears interest, at LFS’s option, at either the Term SOFR (as defined in the Second A&R Credit Agreement) (with a 0.15% floor) plus 3.10% or the Prime Rate (as defined in the Second A&R Credit Agreement) (with a 3.0% floor), subject to a 50 basis point step-down based on the ratio between the senior debt of the Company and its subsidiaries to the EBITDA of LFS and its subsidiaries for the most recently ended four fiscal quarters.

The Second A&R Wintrust Revolving Loan is secured by (i) a valid, perfected and enforceable lien of the administrative agent on the ownership interests held by each of LFS and Wintrust Guarantors in their respective subsidiaries; and (ii) a valid, perfected and enforceable lien of the administrative agent on each of LFS and Wintrust Guarantors’ personal property, fixtures and real estate, subject to certain exceptions and limitations. Additionally, the re-payment of the Second A&R Wintrust Revolving Loan is jointly and severally guaranteed by each Wintrust Guarantor.

The Second A&R Credit Agreement contains representations and warranties, covenants and events of default that are customary for facilities of this type, as more particularly described in the Second A&R Credit Agreement. The Second A&R Wintrust Revolving Loan also contains three financial maintenance covenants, including (i) a requirement to have as of the last day of each quarter for the senior leverage ratio of LFS and its subsidiaries not to exceed an amount beginning at 2.00 to 1.00, (ii) a fixed charge coverage ratio of not less than 1.20 to 1.00 as of the last day of each fiscal quarter, commencing with the fiscal quarter ending March 31, 2023, and (iii) no unfinanced capital expenditures, except for unfinanced capital expenditures in the ordinary course of business not exceeding in the aggregate $4.0 million during any fiscal year; and no default or event of default (as defined in the Second A&R Credit Agreement) has occurred and is continuing, 50% of any portion of this annual limit, if not expended in the fiscal year for which it is permitted, may be carried over for expenditure in the next following fiscal year as stipulated by the agreement.

As of September 30, 2023, the Company had $10.0 million in borrowings outstanding under the Second A&R Wintrust Revolving Loan. As of December 31, 2022, the Company had no borrowings outstanding under the A&R Wintrust Revolving Loan. During the three and nine months ended September 30, 2023, the maximum outstanding borrowings under either the Company's revolving loan arrangements at any time was $10.0 million during both periods and the average daily balance was approximately $10.0 million and $5.5 million, respectively. For the three and nine months ended September 30, 2023, the Company incurred interest on the Second A&R Wintrust Revolving Loan at a weighted average annual interest rate of 5.72% during both periods, inclusive of the net impact associated with the Company's interest rate swap arrangement.

During the three and nine months ended September 30, 2022, the maximum outstanding borrowings under the A&R Wintrust Revolving Loan at any time was $3.5 million and $9.4 million, respectively, and the average daily balance was approximately $0.2 million and $0.1 million, respectively. For the three and nine months ended September 30, 2022, the Company incurred interest on the A&R Wintrust Revolving Loan at a weighted average annual interest rate of 5.25% and 4.78%, respectively.

At September 30, 2023, the Company had irrevocable letters of credit in the amount of $4.2 million with its lender to secure obligations under its self-insurance program.

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The following is a summary of the applicable margin and commitment fees payable on the Second A&R Wintrust Revolving Loan credit commitment:

Level						Senior Leverage Ratio						Applicable Margin for SOFR Revolver loans						Applicable Margin for Prime Revolving loans						Applicable Margin for commitment fee
I						Greater than 1.00 to 1.00						3.10		%				—		%				0.25		%
II						Less than or equal to 1.00 to 1.00						2.60		%				(0.50)		%				0.25		%

As of September 30, 2023, the Company was in compliance with all financial maintenance covenants as required by the A&R Wintrust Loans.

Sale-Leaseback Financing Transaction

On September 29, 2022, LC LLC and Royal Oak Acquisitions, LLC (the “Purchaser”) consummated the purchase of the real property under a sale and leaseback transaction, with an aggregate value of approximately $7.8 million (a purchase price of approximately $5.4 million and $2.4 million in tenant improvement allowances), pursuant to a purchase agreement under which the Purchaser purchased from LC LLC the Company’s facility and real property in Pontiac, MI (collectively, the “Pontiac Facility”).

In connection with the sale and leaseback transaction, LC LLC and Featherstone St Pontiac MI LLC (the “Landlord”) entered into a Lease Agreement (the “Lease Agreement”), dated September 29, 2022 (the “Lease Effective Date”) for the Pontiac Facility. Commencing on the Lease Effective Date, pursuant to the Lease Agreement, LC LLC has leased the Pontiac Facility, subject to the terms and conditions of the Lease Agreement. The Lease Agreement provides for a term of 25 years (the “Primary Term”). The Lease Agreement also provides LC LLC with the option to extend the Primary Term by two separate renewal terms of five years each (each a “Renewal Term”). Under the terms of the Lease Agreement, the Company’s annual minimum rent is $499,730, payable in monthly installments, subject to annual increases of approximately 2.5% each year under the Primary Term and for each year under the Renewal Terms, if exercised. LC LLC has a one-time option to terminate the Lease Agreement effective on the last day of the fifteenth lease year by providing written notice to the Landlord as more fully set forth in the Lease Agreement. The one-time termination option of the Lease Agreement would require LC LLC to pay to the Landlord a termination fee of approximately $1.7 million.

Pursuant to the terms and conditions set forth in the Lease Agreement, the Landlord has agreed to provide LC LLC with a tenant improvement allowance in an amount up to $2.4 million. LC LLC is responsible for the initial capital outlay and completion of the agreed upon improvement work. The Landlord will subsequently reimburse LC LLC for such items up to the stated allowance amount.

The Company accounted for the sale and leaseback arrangement as a financing transaction in accordance with ASC Topic 842, “Leases,” as the Lease Agreement was determined to be a finance lease. The Company concluded the Lease Agreement met the qualifications to be classified as a finance lease due to the significance of the present value of the lease payments, using an implicit rate of 11.11% to reflect the Company’s incremental borrowing rate associated with the $5.4 million purchase price as of the Lease Agreement date, compared to the fair value of the Pontiac Facility. The implicit rate associated with the aggregate purchase value, inclusive of tenant improvement allowances, was 6.53% as of the Lease Agreement date.

The presence of a finance lease indicates that control of the Pontiac Facility has not transferred to the Purchaser and, as such, the transaction was deemed a failed sale-leaseback and must be accounted for as a financing arrangement. As a result of this determination, the Company is viewed as having received the sale proceeds from the Purchaser in the form of a hypothetical loan collateralized by its leased facilities. The hypothetical loan is payable as principal and interest in the form of “lease payments” to the Purchaser. Principal repayments are recorded as a reduction to the financing liability. The Company will not derecognize the Pontiac Facility from its books for accounting purposes until the lease ends. No gain or loss was recognized under GAAP related to the sale and leaseback arrangement.

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Warrants

In conjunction with the Company's initial public offering, the Company issued Public Warrants, Private Warrants and $15 Exercise Price Sponsor Warrants. The Company issued certain Merger Warrants and Additional Merger Warrants in conjunction with the Company's business combination with LHLLC in July 2016 (the “Business Combination”). On July 20, 2021, the Public Warrants, Private Warrants, and Additional Merger Warrants expired by their terms. During the three months ended June 30, 2023, 600,000 $15 Exercise Price Sponsor Warrants and 163,444 Merger Warrants were exercised on a cashless basis by the holders of the warrants, which resulted in the warrants being converted into 167,564 and 45,797 shares of the Company's common stock, respectively. For the period from July 1, 2023 through July 20, 2023, the holders of the Merger Warrants exercised 443,032 warrants on a cashless basis, which resulted in the Merger Warrants being converted into 228,945 shares of the Company's common stock. The remaining 23,167 unexercised Merger Warrants expired by their terms on July 20, 2023.

The following table summarizes the underlying shares of common stock with respect to outstanding warrants:

			September 30, 2023						December 31, 2022
$15 Exercise Price Sponsor Warrants(1)(2)			—						600,000
Merger Warrants(3)(4)			—						629,643
Total			—						1,229,643

(1)    Exercisable for one share of common stock at an exercise price of $15.00 per share (“$15 Exercise Price Sponsor Warrants”).

(2)    Issued under a warrant agreement dated July 15, 2014, between Continental Stock Transfer and Trust Company, as warrant agent, and the Company.

(3)    Exercisable for one share of common stock at an exercise price of $12.50 per share (“Merger Warrants”).

(4)    Issued to the sellers of LHLLC.

Incentive Plan

Upon the consummation of the Company's Business Combination, the Company adopted an omnibus incentive plan (the “Omnibus Incentive Plan”) pursuant to which equity awards may be granted thereunder.

On March 25, 2022, the Board of Directors approved certain amendments to the Company's Omnibus Incentive Plan (the “2022 Amended and Restated Omnibus Incentive Plan”) to increase the number of shares of the Company's common stock that may be issued pursuant to awards by 350,000, for a total of 2,600,000 shares, and extended the term of the plan so that it will expire on the tenth anniversary of the date the stockholders approve the 2022 Amended and Restated Omnibus Incentive Plan. The amendments were approved by the Company's stockholders at the Annual Meeting held on June 22, 2022.

On March 29, 2023, the Board of Directors approved certain amendments to the Company's Omnibus Incentive Plan (the “2023 Amended and Restated Omnibus Incentive Plan”) to increase the number of shares of the Company's common stock that may be issued pursuant to awards by 450,000, for a total of 3,050,000 shares, and extended the term of the plan so that it will expire on the tenth anniversary of the date the stockholders approve the 2023 Amended and Restated Omnibus Incentive Plan. The amendments were acted upon by the Company's stockholders at the Annual Meeting held on June 22, 2023.

See Note 14 for a discussion of the Company's management incentive plans for restricted stock units (“RSUs”) granted, vested, forfeited and remaining unvested.

Share Repurchase Program

In September 2022, the Company announced that its Board of Directors approved a share repurchase program (the “Share Repurchase Program”) to repurchase shares of its common stock for an aggregate purchase price not to exceed $2.0 million. The share repurchase authority was valid through September 29, 2023. Share repurchases may have been executed through various means, including, without limitation, open market transactions, privately negotiated transactions or by other means in accordance with federal securities laws. The Share Repurchase Program did not obligate the Company to acquire any particular amount of common stock, and the program may have been suspended or terminated by the Company at any time at its discretion without prior notice. As of September 30, 2023, the Company has made share repurchases of approximately $2.0 million under its Share Repurchase Program.

Employee Stock Purchase Plan

Upon approval of the Company's stockholders on May 30, 2019, the Company adopted the Limbach Holdings, Inc. 2019 Employee Stock Purchase Plan (the “ESPP”). On January 1, 2020, the ESPP went into effect. The ESPP enables eligible employees, as defined by the ESPP, the right to purchase the Company's common stock through payroll deductions during

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The Company measures the fair value of financial assets and liabilities in accordance with ASC Topic 820 – Fair Value Measurements and Disclosures, which defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements. ASC Topic 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value and requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows:

•Level 1 — inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that are accessible at the measurement date;

•Level 2 — inputs other than quoted prices included in Level 1 that are observable for the asset or liability either directly or indirectly such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities; and

•Level 3 — unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

The Company believes that the carrying amounts of its financial instruments, including cash and cash equivalents, trade accounts receivable and accounts payable, consist primarily of instruments without extended maturities, which approximate fair value primarily due to their short-term maturities and low risk of counterparty default. The Company considers all highly liquid investments purchased with a maturity of 90 days or less on the date of purchase to be cash equivalents. Cash equivalents as of September 30, 2023 consisted of overnight repurchase agreements in which cash from the Company's main operating checking account is invested overnight in highly liquid, short term investments, one U.S. Treasury Bill and certain investments in money market funds sponsored by a large financial institution. The Company had no such investments as of December 31, 2022. For the three and nine months ending September 30, 2023, the Company recognized interest income in the aggregate of approximately $0.4 million and $0.6 million associated with its overnight repurchase agreements, U.S. Treasury Bills and money market funds, respectively. The Company has not experienced any losses in its cash and cash equivalents and management believes the Company is not exposed to significant credit risk with respect to such accounts.

									Fair Value at Reporting Date Using
(in thousands)			September 30, 2023						Level 1						Level 2						Level 3
Cash equivalents:
Overnight repurchase agreements			$	41,687					$	41,687
U.S. Treasury Bills			10,000						10,000						$	—					$	—
Money market fund			3,750						3,750						—						—
Total			$	55,437					$	55,437					$	—					$	—

Second A&R Wintrust Revolving Loan

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The Company also believes that the carrying value of the Second A&R Wintrust Revolving Loan approximates its respective fair value due to the variable rate on such debt. As of September 30, 2023, the Company determined that the fair value of the Second A&R Wintrust Revolving Loan was $10.0 million. Such fair value was determined using discounted estimated future cash flows using level 3 inputs.

Earnout Payments

As a part of the total consideration for the Jake Marshall Transaction, the former owners of JMLLC and CSLLC may receive up to an aggregate of $6.0 million in cash, consisting of two tranches of $3.0 million, as defined in the purchase agreement, if the gross profit of the acquired companies equals or exceeds $10.0 million in (i) the approximately 12-month period from closing through December 31, 2022 (the “2022 Jake Marshall Earnout Period”) or (ii) fiscal year 2023 (the “2023 Jake Marshall Earnout Period”), respectively (collectively, the “Jake Marshall Earnout Payments”). To the extent, however, that the gross profit of the acquired companies is less than $10.0 million, but exceeds $8.0 million, during any of the 2022 Jake Marshall Earnout Period or 2023 Jake Marshall Earnout Period, the $3.0 million amount will be prorated for such period. The Company initially recognized $3.1 million in contingent consideration, of which the entire balance was included in other long-term liabilities in the Company’s condensed consolidated balance sheets on December 2, 2021. The fair value of contingent Jake Marshall Earnout Payments is based on generating growth rates on the projected gross margins of the acquired entities and calculating the associated contingent payments based on achieving the earnout targets, which are reassessed each reporting period. In April 2023, the Company made a $3.0 million payment to the former owners of JMLLC and CSLLC related to the 2022 Jake Marshall Earnout Period. Based on the Company’s ongoing assessment of the fair value of contingent earnout liabilities, the Company recorded a net increase in the estimated fair value of such liabilities of $0.2 million and $0.5 million for the three and nine ended September 30, 2023, respectively, which was presented in change in fair value of contingent consideration in the Company's condensed consolidated statements of operations. During the three and nine months ended September 30, 2022, the Company recorded a net increase in the estimated fair value of such liabilities of $0.4 million and $1.2 million, respectively. The Company determined the fair value of the Earnout Payments by utilizing the Monte Carlo Simulation method, which represents a Level 3 measurement.

As a part of the total consideration for the ACME Transaction, the Company recognized $1.1 million in contingent consideration on the Effective Date. The fair value of contingent ACME Earnout Payments is based on generating growth rates on the projected gross margins of the Acquired Company and calculating the associated contingent payments based on achieving the earnout targets, which are reassessed each reporting period. The Company determined the initial fair value of the ACME Earnout Payments based on the Monte Carlo Simulation method, which represented a Level 3 measurement. As of the Effective Date, the ACME Earnout Payments associated with the ACME Transaction were valued utilizing discount rates between 8.65% and 14.49%. The discount rates were calculated using the build-up method with a risk-free rate commensurate with the term of the ACME Earnout Payments based on the U.S. Treasury Constant Maturity Yield and certain metric risk premiums determined with reference to a long-term risk free rate, a weighted average cost of capital and certain adjustments for operational leverage.

The following table presents the carrying values of the Company's contingent earnout payment obligations included in the accompanying condensed consolidated balance sheets, which approximated fair value at September 30, 2023 and December 31, 2022.

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									Fair Value at Reporting Date Using
(in thousands)			September 30, 2023						Level 1						Level 2						Level 3
Accrued expenses and other current liabilities:
2023 Jake Marshall Earnout Period			$	2,838					$	—					$	—					$	2,838
First ACME Earnout Period			12						—						—						12
Other long-term liabilities:
Second ACME Earnout Period			1,109						—						—						1,109
Total			$	3,959					$	—					$	—					$	3,959
									Fair Value at Reporting Date Using
			December 31, 2022						Level 1						Level 2						Level 3
Accrued expenses and other current liabilities:
2022 Jake Marshall Earnout Period (1)			$	2,859					$	—					$	—					$	2,859
Other long-term liabilities:			—
2023 Jake Marshall Earnout Period			2,515						—						—						2,515
Total			$	5,374					$	—					$	—					$	5,374

(1)    In April 2023, the Company made a $3.0 million payment to the former owners of JMLLC and CSLLC related to the 2022 Jake Marshall Earnout Period.

Interest Rate Swap

The fair value of the interest rate swap is determined using widely accepted valuation techniques and reflects the contractual terms of the interest rate swap including the period to maturity, and while there are no quoted prices in active markets, it uses observable market-based inputs, including interest rate curves and implied volatilities. The fair value analysis also considers a credit valuation adjustment to reflect nonperformance risk of both the Company and the single counterparty. The fair value of the interest rate contract has been determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The interest rate swap is classified as a Level 2 item within the fair value hierarchy. As of September 30, 2023, the Company determined that the fair value of the interest rate swap was approximately $0.5 million and is recognized in other assets on the Company's condensed consolidated balance sheets. For the three and nine months ended September 30, 2023, the Company recognized a gain of approximately $0.1 million and $0.2 million, respectively, on its condensed consolidated statements of operations associated with the change in fair value of the interest rate swap arrangement. For both the three and nine months ended September 30, 2022, the Company recognized a gain of $0.3 million on its condensed consolidated statements of operations associated with the change in fair value of the interest rate swap arrangement.

Earnings per Share

The Company calculates earnings per share in accordance with ASC Topic 260 - Earnings Per Share (“EPS”). Basic earnings per common share applicable to common stockholders is computed by dividing earnings applicable to common stockholders by the weighted-average number of common shares outstanding and assumed to be outstanding. Diluted EPS assumes the dilutive effect of outstanding common stock warrants, shares issued in conjunction with the Company’s ESPP and RSUs, all using the treasury stock method.

The following table sets forth the computation of the basic and diluted earnings per share attributable to the Company's common shareholders for the three and nine months ended September 30, 2023 and 2022:

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						Three Months Ended September 30,												Nine Months Ended September 30,
(in thousands, except per share amounts)						2023						2022						2023						2022
EPS numerator:
Net income						$	7,192					$	3,641					$	15,505					$	2,991
EPS denominator:
Weighted average shares outstanding – basic						10,963						10,445						10,696						10,430
Impact of dilutive securities						826						245						976						165
Weighted average shares outstanding – diluted						11,789						10,690						11,672						10,595
EPS:
Basic						$	0.66					$	0.35					$	1.45					$	0.29
Diluted						$	0.61					$	0.34					$	1.33					$	0.28

The following table summarizes the securities that were antidilutive or out-of-the-money, and therefore, were not included in the computations of diluted income per common share:

			Three Months Ended September 30,												Nine Months Ended September 30,
			2023						2022						2023						2022
Out-of-the-money warrants (see Note 7)			—						1,229,643						—						1,229,643
Service-based RSUs (See Note 14)			—						56						49						3,818
Performance and market-based RSUs(1)			—						197						153						842
Employee Stock Purchase Plan			33						233						1,114						1,301
Total			33						1,230,129						1,316						1,235,604

(1)    For the three and nine months ended September 30, 2022, certain MRSU awards (each defined in Note 14) were not included in the computation of diluted income per common share because the performance and market conditions were not satisfied during the periods and would not be satisfied if the reporting date was at the end of the contingency period.

The Company is taxed as a C corporation.

For interim periods, the provision for income taxes (including federal, state, local and foreign taxes) is calculated based on the estimated annual effective tax rate, adjusted for certain discrete items for the full fiscal year. Cumulative adjustments to the Company's estimate are recorded in the interim period in which a change in the estimated annual effective rate is determined. Each quarter the Company updates its estimate of the annual effective tax rate, and if its estimated tax rate changes, the Company makes a cumulative adjustment.

The following table presents our income tax provision and our income tax rate for the three and nine months ended September 30, 2023 and 2022.

						Three Months Ended September 30,												Nine Months Ended September 30,
(in thousands, except percentages)						2023						2022						2023						2022
Income tax provision						$	2,760					$	1,654					$	5,407					$	1,275
Income tax rate						27.7		%				31.2		%				25.9		%				29.9		%

The U.S. federal statutory tax rate was 21% for each of the three and nine months ended September 30, 2023 and 2022. The difference between the U.S. federal statutory tax rate and the Company’s effective tax rate period over period was primarily due to state income taxes, tax credits, other permanent adjustments and discrete tax items.

No valuation allowance was required as of September 30, 2023 or December 31, 2022.

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As discussed in Note 1, the Company operates in two segments, (i) GCR, in which the Company generally manages new construction or renovation projects that involve primarily HVAC, plumbing, or electrical services awarded to the Company by general contractors or construction managers, and (ii) ODR, in which the Company provides maintenance or service primarily on HVAC, plumbing or electrical systems, building controls and specialty contracting projects direct to, or assigned by, building owners or property managers. These segments are reflective of how the Company’s Chief Operating Decision Maker (“CODM”) reviews operating results for the purposes of allocating resources and assessing performance. The Company's CODM is comprised of its President and Chief Executive Officer and Executive Vice President and Chief Financial Officer.

In accordance with ASC Topic 280 – Segment Reporting, the Company has elected to aggregate all of the GCR work performed at branches into one GCR reportable segment and all of the ODR work performed at branches into one ODR reportable segment. All transactions between segments are eliminated in consolidation.

On January 17, 2023, the Company announced its planned transition succession, pursuant to which Charles A. Bacon III stepped down as President and Chief Executive Officer on March 28, 2023, and Michael M. McCann, the Company’s former Executive Vice President and Chief Operating Officer, was appointed President and Chief Executive Officer. Following the transition, the Company revised its segment presentation to align with how Mr. McCann assesses performance and makes resource allocation decisions for its operating segments, which is based on segment revenue and segment gross profit. Selling, general and administrative ("SG&A") expenses are no longer reported on a segment basis as the Company's current CODM does not review discrete segment financial information for SG&A in order to assess performance. Interest expense is not allocated to segments because of the corporate management of debt service.

The Company restated segment information for the historical periods presented herein to conform to the current presentation. This change in segment presentation does not affect the Company’s unaudited condensed consolidated statements of operations, balance sheets or statements of cash flows.

All of the Company’s identifiable assets are located in the United States, which is where the Company is domiciled.

Condensed consolidated segment information for the three and nine months ended September 30, 2023 and 2022 were as follows:

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			Three Months Ended September 30,												Nine Months Ended September 30,
(in thousands)			2023						2022						2023						2022
Statement of Operations Data:
Revenue:
GCR			$	61,936					$	62,653					$	190,329					$	200,921
ODR			65,832						59,704						183,330						152,378
Total revenue			127,768						122,357						373,659						353,299
Gross profit:
GCR			11,970						9,648						33,560						26,700
ODR			19,274						15,206						52,424						37,814
Total gross profit			31,244						24,854						85,984						64,514
Selling, general and administrative(1)			20,967						18,688						62,433						56,113
Change in fair value of contingent consideration			161						386						464						1,151
Amortization of intangibles			288						386						1,054						1,184
Operating income			$	9,828					$	5,394					$	22,033					$	6,066
Less unallocated amounts:
Interest expense			(437)						(547)						(1,615)						(1,511)
Interest income			377						—						624						—
Gain on disposition of property and equipment			68						150						28						262
Loss on early termination of operating lease			—						—						—						(849)
Loss on early debt extinguishment			—						—						(311)						—
Gain on change in fair value of interest rate swap			116						298						153						298
Total unallocated amounts			124						(99)						(1,121)						(1,800)
Income before income taxes			$	9,952					$	5,295					$	20,912					$	4,266

(1)    Included within selling, general and administrative expenses was $1.1 million and $0.8 million of stock based compensation expense for the three months ended September 30, 2023 and 2022, respectively. For the nine months ended September 30, 2023 and 2022, selling, general and administrative expenses included $3.4 million and $2.0 million of stock based compensation expenses, respectively.

The Company does not identify capital expenditures and total assets by segment in its internal financial reports due in part to the shared use of a centralized fleet of vehicles and specialized equipment. Interest expense is also not allocated to segments because of the Company’s corporate management of debt service, including interest.

The Company leases real estate, trucks and other equipment. The determination of whether an arrangement is, or contains, a lease is performed at the inception of the arrangement. Classification and initial measurement of the right-of-use asset and lease liability are determined at the lease commencement date. The Company elected the short-term lease measurement and recognition exemption; therefore, leases with an initial term of 12 months or less are not recorded on the condensed consolidated balance sheets. Instead, the short-term leases are recognized in expense on a straight-line basis over the lease term.

The Company's arrangements include certain non-lease components such as common area and other maintenance for leased real estate, as well as mileage, fuel and maintenance costs related to leased vehicles. For all leased asset classes, the Company has elected to not separate non-lease components from lease components and will account for each separate lease component and non-lease component associated with the lease as a single lease component. The Company does not guarantee any residual value in its lease agreements, and there are no material restrictions or covenants imposed by lease arrangements. Real estate leases typically include one or more options to extend the lease. The Company regularly evaluates the renewal options, and when they are reasonably certain of exercise, the Company includes the renewal period in its lease term. For the Company's leased vehicles, the Company uses the interest rate implicit in its leases with the lessor to discount lease payments at the lease commencement date. When the implicit rate is not readily available, as is the case with the Company's real estate leases, the Company uses quoted borrowing rates on its secured debt.

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Related Party Lease Agreements. In conjunction with the closing of the Jake Marshall Transaction, the Company entered into an operating lease for certain land and facilities owned by a former member of JMLLC who became a full-time employee of the Company. The lease term is 10 years and includes an option to extend the lease for two successive periods of two years each through November 2035. Base rent for the term of the lease is $37,500 per month for the first five years with payment commencing on January 1, 2022. The fixed rent payment is escalated to $45,000 per month for years 6 through 10 of the lease term. Fixed rent payments for the extension term shall be increased from $45,000 by the percentage increase, if any, in the consumer price index from the lease commencement date. In addition, under the agreement, the Company is required to pay its share of estimated property taxes and operating expenses, both of which are variable lease expenses.

In conjunction with the closing of the ACME Transaction, the Company entered into an operating lease for certain land and facilities owned by a former member of ACME who became a full-time employee of the Company. The lease term of the lease runs through December 31, 2024 and includes an option to extend the lease for one successive period of one year through December 2025. Base rent for the term of the lease is $17,000 per month for the first six months with payment commencing on July 1, 2023. The fixed rent payment is escalated to $18,000 per month for the twelve month period ending December 31, 2024. Fixed rent payments for the extension term shall be increased to $19,000. In addition, under the agreement, the Company is required to pay its share of estimated property taxes and operating expenses, both of which are variable lease expenses.

Southern California Sublease. In June, 2021, the Company entered into a sublease agreement with a third party for the entire ground floor of its leased space in Southern California, consisting of 71,787 square feet. Under the terms of the sublease agreement, the sublessee is obligated to pay the Company base rent of approximately $0.6 million per year, which is subject to a 3.0% annual rent increase, plus certain operating expenses and other costs. The initial lease term commenced in September 2021 and continues through April 30, 2027. As of September 30, 2023, the Company remains obligated under the original lease for such office space and, in the event the sublessee of such office space fails to satisfy its obligations under the sublease, the Company would be required to satisfy its obligations directly to the landlord under such original lease.

In addition, during the first quarter of 2022, the Company entered into an amendment to the aforementioned sublease agreement, which, among other things, expanded the sublease premises to include the entire second floor of its leased space in Southern California, consisting of 16,720 square feet. Under the terms of the amended sublease agreement, the sublessee is obligated to pay the Company base rent of approximately $0.8 million per year, which is subject to a 3.0% annual rent increase, plus certain operating expenses and other costs. The amended sublease term commenced in March 2022 and continues through April 30, 2027. For the three and nine months ended September 30, 2023, the Company recorded approximately $0.3 million and $0.5 million, respectively, of income in selling, general and administrative expenses related to this sublease agreement. For the three and nine months ended September 30, 2022, the Company recorded approximately $0.2 million and $0.4 million, respectively, of income in selling, general and administrative expenses related to this sublease agreement.

Pittsburgh Lease Termination. In March, 2022, the Company entered into a lease termination agreement (the “Lease Termination Agreement”) to terminate, effective March 31, 2022, the lease associated with the Company’s office space located in Pittsburgh, Pennsylvania, which previously served as its corporate headquarters. Absent the Lease Termination Agreement, the lease would have expired in accordance with its terms in July 2025. Pursuant to the Lease Termination Agreement, in exchange for allowing the Company to terminate the lease early, the Company agreed to pay a termination fee in the aggregate of approximately $0.7 million in 16 equal monthly installments commencing on April 1, 2022. The Company recognized the full termination fee expense during the first quarter of 2022.

In connection with the lease termination, the Company recognized a gain of $0.1 million associated with the derecognition of the operating lease right-of-use asset and corresponding operating lease liabilities associated with the operating lease and recorded a $0.1 million loss on the disposal of leasehold improvements and moving expenses.

The following table summarizes the lease amounts included in the Company's condensed consolidated balance sheets:

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(in thousands)			Classification on the Condensed Consolidated Balance Sheets						September 30, 2023						December 31, 2022
Assets
Operating			Operating lease right-of-use assets(1)						$	15,845					$	18,288
Finance			Property and equipment, net(2)(3)						9,217						7,402
Total lease assets									$	25,062					$	25,690
Liabilities
Current
Operating			Current operating lease liabilities						$	3,562					$	3,562
Finance			Current portion of long-term debt						2,472						2,135
Noncurrent
Operating			Long-term operating lease liabilities						13,240						15,643
Finance			Long-term debt(4)						9,828						8,170
Total lease liabilities									$	29,102					$	29,510

(1)     Operating lease assets are recorded net of accumulated amortization of $13.0 million at September 30, 2023 and $12.2 million at December 31, 2022.

(2)    Finance lease vehicle assets are recorded net of accumulated amortization of $4.9 million at September 30, 2023 and $6.0 million at December 31, 2022.

(3)    Includes approximately $2.5 million and $2.6 million of net property assets associated with the Company's Pontiac Facility as of September 30, 2023 and December 31, 2022, respectively.

(4)    Includes approximately $5.4 million associated with the Company's sale and leaseback financing transaction. See Note 6 for further detail.

The following table summarizes the lease costs included in the Company's condensed consolidated statements of operations for the three and nine months ended September 30, 2023 and 2022:

									Three Months Ended September 30,												Nine Months Ended September 30,
(in thousands)			Classification on the Condensed Consolidated Statement of Operations						2023						2022						2023						2022
Operating lease cost			Cost of revenue(1)						$	543					$	654					$	1,626					$	2,005
Operating lease cost			Selling, general and administrative(1)						635						622						1,892						1,957
Finance lease cost
Amortization			Cost of revenue(2)						714						684						2,012						2,020
Interest			Interest expense, net(2)						113						68						265						200
Total lease cost									$	2,005					$	2,028					$	5,795					$	6,182

(1)    Operating lease costs recorded in cost of revenue included $0.1 million and $0.2 million of variable lease costs for the three months ended September 30, 2023 and 2022, respectively, and $0.3 million and $0.4 million for the nine months ended September 30, 2023 and 2022, respectively. In addition, $0.2 million of variable lease costs are included in selling, general and administrative for each of the three months ended September 30, 2023 and 2022, and $0.4 million for each of the nine months ended September 30, 2023 and 2022. These variable costs consist of the Company's proportionate share of operating expenses, real estate taxes and utilities.

(2)     Finance lease costs recorded in cost of revenue include variable lease costs of $0.9 million and $1.0 million for the three months ended September 30, 2023 and 2022, respectively, and $2.7 million and $2.8 million for the nine months ended September 30, 2023 and 2022, respectively. These variable lease costs consist of fuel, maintenance, and sales tax charges.

The future undiscounted minimum finance lease payments, as reconciled to the discounted minimum lease obligation indicated on the Company’s condensed consolidated balance sheets within current and long-term debt, less interest, and under current and long-term operating leases, less imputed interest, as of September 30, 2023 were as follows (in thousands):

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						Finance Lease Obligations																		Operating Lease Obligations
Year ending:						Vehicles						Pontiac Facility						Total Finance						Non-Related Party						Related Party(1)						Total Operating						Sublease Receipts(2)
Remainder of 2023						$	813					$	128					$	941					$	1,347					$	218					$	1,565					$	224
2024						2,624						515						3,139						3,322						666						3,988						912
2025						2,083						528						2,611						2,787						450						3,237						939
2026						1,567						542						2,109						2,670						450						3,120						967
2027						636						555						1,191						1,693						540						2,233						326
Thereafter						—						14,302						14,302						1,536						4,275						5,811						—
Total minimum lease payments						7,723						16,570						24,293						13,355						6,599						19,954						$	3,369
Financing Component (3)						(774)						(11,219)						(11,993)						(1,676)						(1,476)						(3,152)
Net present value of minimum lease payments						6,949						5,351						12,300						11,679						5,123						16,802
Less: current portion of finance and operating lease obligations						(2,472)						—						(2,472)						(3,111)						(451)						(3,562)
Long-term finance and operating lease obligations						$	4,477					$	5,351					$	9,828					$	8,568					$	4,672					$	13,240

(1)    Associated with the aforementioned related party leases entered into with former members of JMLLC and ACME.

(2)    Associated with the aforementioned third party sublease.

(3)     The financing component for finance lease obligations represents the interest component of finance leases that will be recognized as interest expense in future periods. The financing component for operating lease obligations represents the effect of discounting the lease payments to their present value.

The following is a summary of the lease terms and discount rates as of:

			September 30, 2023						December 31, 2022
Weighted average lease term (in years):
Operating			6.50						6.98
Finance (1)			3.12						2.73
Weighted average discount rate:
Operating			4.91		%				4.76		%
Finance (1)			6.66		%				5.06		%

(1)     Excludes the weighted average lease term and weighted average discount rate associated with the aforementioned sale-leaseback financing transaction, which has a Primary Term of 25 years and utilized an implicit rate of 11.11%. See Note 6 for further detail.

The following is a summary of other information and supplemental cash flow information related to finance and operating leases:

						Nine months ended September 30,
(in thousands)						2023						2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases						$	3,478					$	3,890
Operating cash flows from finance leases						227						200
Financing cash flows from finance leases						2,032						2,051
Right-of-use assets exchanged for lease liabilities:
Operating leases						1,043						—
Finance leases						4,062						2,171
Right-of-use assets disposed or adjusted modifying operating leases liabilities						(643)						2,396
Right-of-use assets disposed or adjusted modifying finance leases liabilities						$	(77)					(77)

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Legal. The Company is continually engaged in administrative proceedings, arbitrations, and litigation with owners, general contractors, suppliers, employees, former employees and other unrelated parties, all arising in the ordinary courses of business. The ultimate resolution of these contingencies could, individually or in the aggregate, be material to the condensed consolidated financial statements. In the opinion of the Company’s management, the current belief is that the results of these actions will not have a material adverse effect on the financial position, results of operations, or cash flows of the Company.

On January 23, 2020, plaintiff, Bernards Bros. Inc. (“Bernards”), filed a complaint against the Company in Superior Court of the State of California for the County of Los Angeles. The complaint alleges that the Company's Southern California business unit refused to honor a proposal made to Bernards to act as a subcontractor on a construction project, and that, as a result of the wrongful failure to honor the proposal, Bernards suffered damages in excess of $3.0 million plus interest, including alleged increased costs for hiring a different subcontractor to perform the work. The Company has vigorously defended the suit. Per the agreement of the Company and Bernards, in January 2022, the Court appointed a private referee to manage the case and adjudicate the dispute. A trial took place before the referee in January 2023, and on April 30, 2023, the referee issued an Amended Statement of Decision awarding Bernards approximately $2.2 million. As of December 31, 2022, the Company had determined that a loss was probable, and, as such, recorded an estimated loss contingency in the amount of $2.2 million, which is included in accrued expenses and other current liabilities reported within the Company’s consolidated balance sheets. In addition, the estimated loss contingency was recorded within selling, general and administrative expenses on the Company’s consolidated statements of operations. The Company is currently evaluating its options to appeal the referee's decisions.

Surety. The terms of its construction contracts frequently require that the Company obtain from surety companies, and provide to its customers, payment and performance bonds (“Surety Bonds”) as a condition to the award of such contracts. The Surety Bonds secure the Company's payment and performance obligations under such contracts, and the Company has agreed to indemnify the surety companies for amounts, if any, paid by them in respect of Surety Bonds issued on its behalf. In addition, at the request of labor unions representing certain of the Company's employees, Surety Bonds are sometimes provided to secure obligations for wages and benefits payable to or for such employees. Public sector contracts require Surety Bonds more frequently than private sector contracts, and accordingly, the Company's bonding requirements typically increase as the amount of public sector work increases. As of September 30, 2023, the Company had approximately $99.7 million in surety bonds outstanding. The Surety Bonds are issued by surety companies in return for premiums, which vary depending on the size and type of bond.

Collective Bargaining Agreements. Many of the Company’s craft labor employees are covered by collective bargaining agreements. The agreements require the Company to pay specified wages, provide certain benefits and contribute certain amounts to multi-employer pension plans. If the Company withdraws from any of the multi-employer pension plans or if the plans were to otherwise become underfunded, the Company could incur additional liabilities related to these plans. Although the Company has been informed that some of the multi-employer pension plans to which it contributes have been classified as “critical” status, the Company is not currently aware of any significant liabilities related to this issue.

Self-insurance. The Company is substantially self-insured for workers’ compensation and general liability claims, in the view of the relatively high per-incident deductibles the Company absorbs under its insurance arrangements for these risks. The Company purchases workers’ compensation and general liability insurance under policies with per-incident deductibles of $250,000 per occurrence and a $4.4 million maximum aggregate deductible loss limit per year. Losses incurred over primary policy limits are covered by umbrella and excess policies up to specified limits with multiple excess insurers. The Company accrues for the unfunded portion of costs for both reported claims and claims incurred but not reported. The liability for unfunded reported claims and future claims is reflected on the consolidated balance sheets as current and non-current liabilities. The liability is determined by establishing a reserve for each reported claim on a case-by-case basis based on the nature of the claim and historical loss experience for similar claims plus an allowance for the cost of incurred but not reported claims. The current portion of the liability is included in accrued expenses and other current liabilities on the consolidated balance sheets. The non-current portion of the liability is included in other long-term liabilities on the consolidated balance sheets.

The Company is self-insured related to medical and dental claims under policies with annual per-claimant and annual aggregate stop-loss limits. The Company accrues for the unfunded portion of costs for both reported claims and claims incurred but not reported. The liability for unfunded reported claims and future claims is reflected on the consolidated balance sheets as a current liability in accrued expenses and other current liabilities.

The components of the self-insurance liability as of September 30, 2023 and December 31, 2022 are as follows:

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(in thousands)			September 30, 2023						December 31, 2022
Current liability — workers’ compensation and general liability			$	99					$	158
Current liability — medical and dental			422						557
Non-current liability			746						343
Total liability			$	1,267					$	1,058
Restricted cash			$	65					$	113

The restricted cash balance represents an imprest cash balance set aside for the funding of workers' compensation and general liability insurance claims. This amount is replenished either when depleted or at the beginning of each month.

The Company initially adopted the Omnibus Incentive Plan on July 20, 2016 for the purpose of: (a) encouraging the profitability and growth of the Company through short-term and long-term incentives that are consistent with the Company’s objectives; (b) giving participants an incentive for excellence in individual performance; (c) promoting teamwork among participants; and (d) giving the Company a significant advantage in attracting and retaining key employees, directors and consultants. To accomplish such purposes, the Omnibus Incentive Plan, and such subsequent amendments to the Omnibus Incentive Plan, provides that the Company may grant options, stock appreciation rights, restricted shares, RSUs, performance-based awards (including performance-based restricted shares and restricted stock units), other share based awards, other cash-based awards or any combination of the foregoing.

Following the approval of the 2023 Amended and Restated Omnibus Incentive Plan, the Company has reserved 3,050,000 shares of its common stock for issuance. The number of shares issued or reserved pursuant to the Omnibus Incentive Plan will be adjusted by the plan administrator, as they deem appropriate and equitable, as a result of stock splits, stock dividends, and similar changes in the Company’s common stock. In connection with the grant of an award, the plan administrator may provide for the treatment of such award in the event of a change in control. All awards are made in the form of shares only.

Service-Based Awards

The Company grants service-based stock awards in the form of RSUs. Service-based RSUs granted to executives, employees, and non-employee directors vest ratably, on an annual basis, over three years and in the case of certain awards to non-employee directors, one year. The grant date fair value of the service-based awards was equal to the closing market price of the Company’s common stock on the date of grant. For both the three months ended September 30, 2023 and 2022, the Company recognized $0.5 million of stock-based compensation expense related to outstanding service-based RSUs. For both the nine months ended September 30, 2023 and 2022, the Company recognized $1.2 million of stock-based compensation expense related to outstanding service-based RSUs during both periods.

The following table summarizes the Company's service-based RSU activity for the nine months ended September 30, 2023:

			Awards						Weighted-Average Grant Date Fair Value
Unvested at December 31, 2022			280,275						$	9.06
Granted			164,413						11.94
Vested			(163,354)						8.58
Forfeited			(42,131)						10.63
Unvested at September 30, 2023			239,203						$	11.09

Performance-Based Awards

The Company grants performance-based restricted stock units (“PRSUs”) under which shares of the Company’s common stock may be earned based on the Company’s performance compared to defined metrics. The number of shares earned under a performance award may vary from zero to 150% of the target shares awarded, based upon the Company’s performance compared to the metrics. The metrics used for the grant are determined by the Company’s Compensation Committee of the Board of Directors and are based on internal measures such as the achievement of certain predetermined adjusted EBITDA, EPS growth and EBITDA margin performance goals over a three year period.

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The Company recognizes stock-based compensation expense for these awards over the vesting period based on the projected probability of achievement of the performance conditions as of the end of each reporting period during the performance period and may periodically adjust the recognition of such expense, as necessary, in response to any changes in the Company’s forecasts with respect to the performance conditions. For the three months ended September 30, 2023 and 2022, the Company recognized $0.7 million and $0.3 million, respectively, of stock-based compensation expense related to outstanding PRSUs. For the nine months ended September 30, 2023 and 2022, the Company recognized $2.2 million and $0.7 million, respectively, of stock-based compensation expense related to outstanding PRSUs.

The following table summarizes the Company's PRSU activity for the nine months ended September 30, 2023:

			Awards						Weighted-Average Grant Date Fair Value
Unvested at December 31, 2022			497,940						$	8.32
Granted			289,092						12.77
Performance factor adjustment(1)			32,327						4.29
Vested			(121,827)						4.29
Forfeited			(116,911)						9.81
Unvested at September 30, 2023			580,621						$	10.85

(1)     Performance-based awards covering the three year period ended December 31, 2022 were paid out in the first quarter of 2023 based on the approval of the Company's Compensation Committee. The performance factor during the measurement period used to determine compensation payouts was 136.13% of the pre-defined metric target of 100%, which resulted in a positive performance factor adjustment and the issuance of 32,327 of additional awards associated with the original grant.

Market-Based Awards

The vesting of the Company's market-based RSU (“MRSUs”) was contingent upon the Company’s closing price of a share of the Company's common stock on the Nasdaq Capital market, or such other applicable principal securities exchange or quotation system, achieving at least $18.00 over a period of eighty consecutive trading days during the three-year period commencing on August 1, 2018 and concluding on July 31, 2021. On September 4, 2020, the Compensation Committee of the Board of Directors of the Company approved amendments to modify the MRSUs to extend the measurement period to July 16, 2022. In addition to the market performance-based vesting condition, the vesting of such restricted stock unit was subject to continued employment from August 1, 2017 through the later of July 31, 2019 or the date on which the Compensation Committee certifies the achievement of the performance goal. The Company accounted for this amendment as a Type I modification and recognized approximately $0.2 million of incremental stock-based compensation expense over 1.26 years from the modification date based on an updated Monte Carlo simulation model. These awards expired on July 16, 2022 as the MRSU award market condition was not achieved.

Stock-Based Compensation Expense

Total recognized stock-based compensation expense amounted to $1.1 million and $0.8 million for the three months ended September 30, 2023 and 2022, respectively. For the nine months ended September 30, 2023 and 2022, the Company recognized stock-based compensation expense of $3.4 million and $2.0 million, respectively. The aggregate fair value as of the vest date of RSUs that vested during the nine months ended September 30, 2023 and 2022 was $3.8 million and $1.1 million, respectively. Total unrecognized stock-based compensation expense related to unvested RSUs which are probable of vesting was $3.9 million at September 30, 2023. These costs are expected to be recognized over a weighted average period of 1.68 years.

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v3.23.3

Cover - shares	9 Months Ended
	Sep. 30, 2023	Nov. 06, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-36541
Entity Registrant Name	LIMBACH HOLDINGS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-5399422
Entity Address, Address Line One	797 Commonwealth Drive
Entity Address, City or Town	Warrendale
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15086
City Area Code	412
Local Phone Number	359-2100
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	LMB
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		11,003,424
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001606163
Current Fiscal Year End Date	--12-31

v3.23.3

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 57,473	$ 36,001
Restricted cash	65	113
Accounts receivable (net of allowance for credit losses of $295 and net of allowance for doubtful accounts of $234 as of September 30, 2023 and December 31, 2022, respectively)	103,511	124,442
Contract assets	47,853	61,453
Income tax receivable	0	95
Other current assets	5,346	3,886
Total current assets	214,248	225,990
Property and equipment, net	19,377	18,224
Intangible assets, net	16,586	15,340
Goodwill	13,703	11,370
Operating lease right-of-use assets	15,845	18,288
Deferred tax asset	4,830	4,829
Other assets	613	515
Total assets	285,202	294,556
Current liabilities:
Current portion of long-term debt	2,472	9,564
Current operating lease liabilities	3,562	3,562
Accounts payable, including retainage	56,589	75,122
Contract liabilities	46,692	44,007
Accrued income taxes	502	1,888
Accrued expenses and other current liabilities	26,724	24,942
Total current liabilities	136,541	159,085
Long-term debt	19,437	21,528
Long-term operating lease liabilities	13,240	15,643
Other long-term liabilities	1,854	2,858
Total liabilities	171,072	199,114
Commitments and contingencies (Note 13)
STOCKHOLDERS’ EQUITY
Common stock, $0.0001 par value; 100,000,000 shares authorized, issued 11,183,076 and 10,471,410, respectively, and 11,003,424 and 10,291,758 outstanding, respectively	1	1
Additional paid-in capital	90,992	87,809
Treasury stock, at cost (179,652 shares at both period ends)	(2,000)	(2,000)
Retained earnings	25,137	9,632
Total stockholders’ equity	114,130	95,442
Total liabilities and stockholders’ equity	$ 285,202	$ 294,556

v3.23.3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Accounts receivable, allowance for credit loss, current	$ 295	$ 234
Common stock, par or stated value per share (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares, issued (in shares)	11,183,076	10,471,410
Common stock, shares, outstanding (in shares)	11,003,424	10,291,758
Treasury stock (in shares)	179,652	179,652

v3.23.3

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue	$ 127,768	$ 122,357	$ 373,659	$ 353,299
Cost of revenue	96,524	97,503	287,675	288,785
Gross profit	31,244	24,854	85,984	64,514
Operating expenses:
Selling, general and administrative	20,967	18,688	62,433	56,113
Change in fair value of contingent consideration	161	386	464	1,151
Amortization of intangibles	288	386	1,054	1,184
Total operating expenses	21,416	19,460	63,951	58,448
Operating income	9,828	5,394	22,033	6,066
Other income (expenses):
Interest expense	(437)	(547)	(1,615)	(1,511)
Interest income	377	0	624	0
Gain on disposition of property and equipment	68	150	28	262
Loss on early termination of operating lease	0	0	0	(849)
Loss on early debt extinguishment	0	0	(311)	0
Gain on change in fair value of interest rate swap	116	298	153	298
Total other income (expenses)	124	(99)	(1,121)	(1,800)
Income before income taxes	9,952	5,295	20,912	4,266
Income tax provision	2,760	1,654	5,407	1,275
Net income	$ 7,192	$ 3,641	$ 15,505	$ 2,991
Earnings per common share:
Basic (in usd per share)	$ 0.66	$ 0.35	$ 1.45	$ 0.29
Diluted (in usd per share)	$ 0.61	$ 0.34	$ 1.33	$ 0.28
Weighted average number of shares outstanding:
Basic (in shares)	10,962,622	10,444,987	10,695,973	10,429,671
Diluted (in shares)	11,789,137	10,690,434	11,671,819	10,595,061

v3.23.3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Number of Shares	Additional paid-in capital	Treasury stock, at cost	Retained earnings
Beginning balance (in shares) at Dec. 31, 2021		10,304,242
Beginning balance at Dec. 31, 2021	$ 87,838	$ 1	$ 85,004		$ 2,833
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	599		599
Shares issued related to vested restricted stock units (in shares)		105,928
Shares issued related to vested restricted stock units	0
Tax withholding related to vested restricted stock units	(148)		(148)
Shares issued related to employee stock purchase plan (in shares)		12,898
Shares issued related to employee stock purchase plan	98		98
Net (loss) income	(1,516)				(1,516)
Ending balance (in shares) at Mar. 31, 2022		10,423,068
Ending balance at Mar. 31, 2022	86,871	$ 1	85,553		1,317
Beginning balance (in shares) at Dec. 31, 2021		10,304,242
Beginning balance at Dec. 31, 2021	87,838	$ 1	85,004		2,833
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	2,991
Ending balance (in shares) at Sep. 30, 2022		10,447,660
Ending balance at Sep. 30, 2022	92,870	$ 1	87,045		5,824
Beginning balance (in shares) at Mar. 31, 2022		10,423,068
Beginning balance at Mar. 31, 2022	86,871	$ 1	85,553		1,317
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	575		575
Net (loss) income	866				866
Ending balance (in shares) at Jun. 30, 2022		10,423,068
Ending balance at Jun. 30, 2022	88,312	$ 1	86,128		2,183
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	806		806
Shares issued related to employee stock purchase plan (in shares)		24,592
Shares issued related to employee stock purchase plan	111		111
Net (loss) income	3,641				3,641
Ending balance (in shares) at Sep. 30, 2022		10,447,660
Ending balance at Sep. 30, 2022	$ 92,870	$ 1	87,045		5,824
Beginning balance (in shares) at Dec. 31, 2022		10,471,410
Treasury stock (in shares) at Dec. 31, 2022	(179,652)			(179,652)
Beginning balance at Dec. 31, 2022	$ 95,442	$ 1	87,809	$ (2,000)	9,632
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,133		1,133
Shares issued related to vested restricted stock units (in shares)		250,548
Shares issued related to vested restricted stock units	0
Tax withholding related to vested restricted stock units	(428)		(428)
Shares issued related to employee stock purchase plan (in shares)		10,997
Shares issued related to employee stock purchase plan	97		97
Net (loss) income	2,993				2,993
Ending balance (in shares) at Mar. 31, 2023		10,732,955
Treasury stock (in shares) at Mar. 31, 2023				(179,652)
Ending balance at Mar. 31, 2023	$ 99,237	$ 1	88,611	$ (2,000)	12,625
Beginning balance (in shares) at Dec. 31, 2022		10,471,410
Treasury stock (in shares) at Dec. 31, 2022	(179,652)			(179,652)
Beginning balance at Dec. 31, 2022	$ 95,442	$ 1	87,809	$ (2,000)	9,632
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ 15,505
Ending balance (in shares) at Sep. 30, 2023		11,183,076
Treasury stock (in shares) at Sep. 30, 2023	(179,652)
Ending balance at Sep. 30, 2023	$ 114,130	$ 1	90,992	$ (2,000)	25,137
Beginning balance (in shares) at Mar. 31, 2023		10,732,955
Treasury stock (in shares) at Mar. 31, 2023				(179,652)
Beginning balance at Mar. 31, 2023	99,237	$ 1	88,611	$ (2,000)	12,625
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,101		1,101
Shares issued related to exercise of warrants (in shares)		213,361
Shares issued related to the exercise of warrants	0
Net (loss) income	5,320				5,320
Ending balance (in shares) at Jun. 30, 2023		10,946,316
Treasury stock (in shares) at Jun. 30, 2023				(179,652)
Ending balance at Jun. 30, 2023	105,658	$ 1	89,712	$ (2,000)	17,945
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,140		1,140
Shares issued related to vested restricted stock units (in shares)		1,151
Shares issued related to vested restricted stock units	0
Shares issued related to employee stock purchase plan (in shares)		6,664
Shares issued related to employee stock purchase plan	140		140
Shares issued related to exercise of warrants (in shares)		228,945
Shares issued related to the exercise of warrants	0
Net (loss) income	$ 7,192				7,192
Ending balance (in shares) at Sep. 30, 2023		11,183,076
Treasury stock (in shares) at Sep. 30, 2023	(179,652)
Ending balance at Sep. 30, 2023	$ 114,130	$ 1	$ 90,992	$ (2,000)	$ 25,137

v3.23.3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net income	$ 15,505	$ 2,991
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	5,751	6,173
Provision for credit losses / doubtful accounts	186	235
Stock-based compensation expense	3,374	1,980
Noncash operating lease expense	2,843	3,336
Amortization of debt issuance costs	69	100
Deferred income tax provision	(1)	(1,077)
Gain on sale of property and equipment	(28)	(262)
Loss on early termination of operating lease	0	849
Loss on change in fair value of contingent consideration	464	1,151
Loss on early debt extinguishment	311	0
Gain on change in fair value of interest rate swap	(153)	(298)
Changes in operating assets and liabilities:
Accounts receivable	21,896	(21,906)
Contract assets	14,014	18,597
Other current assets	(1,459)	698
Accounts payable, including retainage	(18,703)	(53)
Prepaid income taxes	95	(101)
Accrued taxes payable	(1,386)	1,763
Contract liabilities	2,312	15,810
Operating lease liabilities	(2,803)	(3,264)
Accrued expenses and other current liabilities	1,997	(3,612)
Payment of contingent consideration liability in excess of acquisition-date fair value	(1,224)	0
Other long-term liabilities	400	(130)
Net cash provided by operating activities	43,460	22,980
Cash flows from investing activities:
ACME Transaction, net of cash acquired	(4,883)	0
Proceeds from sale of property and equipment	370	442
Purchase of property and equipment	(1,720)	(725)
Net cash used in investing activities	(6,233)	(283)
Cash flows from financing activities:
Payments on Wintrust and A&R Wintrust Term Loans	(21,452)	(11,571)
Proceeds from Wintrust Revolving Loan	10,000	15,194
Payments on Wintrust Revolving Loan	0	(15,194)
Proceeds from financing transaction (see Note 6)	0	5,400
Payments on financing liability	0	(7)
Payment of contingent consideration liability up to acquisition-date fair value	(1,776)	0
Payments on finance leases	(1,991)	(2,051)
Payments of debt issuance costs	(50)	(427)
Taxes paid related to net-share settlement of equity awards	(847)	(363)
Proceeds from contributions to Employee Stock Purchase Plan	313	265
Net cash used in financing activities	(15,803)	(8,754)
Increase in cash, cash equivalents and restricted cash	21,424	13,943
Cash, cash equivalents and restricted cash, beginning of period	36,114	14,589
Cash, cash equivalents and restricted cash, end of period	57,538	28,532
Noncash investing and financing transactions:
Earnout liability associated with the ACME Transaction	1,121	0
Right of use assets obtained in exchange for new operating lease liabilities	1,043	0
Right of use assets obtained in exchange for new finance lease liabilities	4,062	2,171
Right of use assets disposed or adjusted modifying operating lease liabilities	(643)	2,396
Right of use assets disposed or adjusted modifying finance lease liabilities	(77)	(77)
Interest paid	1,482	1,425
Cash paid for income taxes	$ 6,718	$ 768

v3.23.3

Business and Organization	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Organization	Business and OrganizationLimbach Holdings, Inc. (the “Company,” “we” or “us”), a Delaware corporation headquartered in Warrendale, Pennsylvania, was formed on July 20, 2016 as a result of a business combination with Limbach Holdings LLC (“LHLLC”). The Company is a building systems solutions firm with expertise in the design, prefabrication, installation, management and maintenance of heating, ventilation, air-conditioning (“HVAC”), mechanical, electrical, plumbing and controls systems. The Company provides comprehensive facility services consisting of mechanical construction, full HVAC service and maintenance, energy audits and retrofits, engineering and design build services, constructability evaluation, equipment and materials selection, offsite/prefabrication construction, and the complete range of sustainable building solutions. The Company’s customers operate in diverse industries including, but not limited to, data centers and healthcare, industrial and light manufacturing, cultural and entertainment, higher education, and life science facilities. The Company operates primarily in the Northeast, Mid-Atlantic, Southeast and Midwest regions of the United States.The Company operates in two segments, (i) General Contractor Relationships (“GCR”), in which the Company generally manages new construction or renovation projects that involve primarily HVAC, plumbing, or electrical services awarded to the Company by general contractors or construction managers, and (ii) Owner Direct Relationships (“ODR”), in which the Company performs owner direct projects and/or provides maintenance or service primarily on HVAC, plumbing or electrical systems, building controls and specialty contracting projects direct to, or assigned by, building owners or property managers. This work is primarily performed under fixed price, modified fixed price, and time and material contracts over periods of typically less than two years.

v3.23.3

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Presentation References in these financial statements to the Company refer collectively to the accounts of Limbach Holdings, Inc. and its wholly-owned subsidiaries, including LHLLC, Limbach Facility Services LLC (“LFS”), Limbach Company LLC (“LC LLC”), Limbach Company LP, Harper Limbach LLC, Harper Limbach Construction LLC, Limbach Facility & Project Solutions LLC, Jake Marshall, LLC (“JMLLC”), Coating Solutions, LLC (“CSLLC”) and ACME Industrial Piping, LLC (“ACME”) for all periods presented, unless otherwise indicated. All intercompany balances and transactions have been eliminated. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the requirements of Form 10-Q and Rule 8-03 of Regulation S-X for smaller reporting companies. Consequently, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. Readers of this report should refer to the consolidated financial statements and the notes thereto included in the Company's most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 8, 2023. Use of Estimates The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements for assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, the reported amounts of revenue and expenses during the reported period, and the accompanying notes. Management believes that its most significant estimates and assumptions have been based on reasonable and supportable assumptions and the resulting estimates are reasonable for use in the preparation of the condensed consolidated financial statements. The Company’s significant estimates include estimates associated with revenue recognition on construction contracts, costs incurred through each balance sheet date, intangibles, property and equipment, fair value accounting for acquisitions, insurance reserves, fair value of contingent consideration arrangements and contingencies. If the underlying estimates and assumptions upon which the condensed consolidated financial statements are based change in the future, actual amounts may differ from those included in the accompanying condensed consolidated financial statements. Unaudited Interim Financial Information The accompanying interim Condensed Consolidated Balance Sheets, Condensed Consolidated Statements of Operations, Condensed Consolidated Statements of Stockholders’ Equity and Condensed Consolidated Statements of Cash Flows for the periods presented are unaudited. Also, within the notes to the condensed consolidated financial statements, the Company has included unaudited information for these interim periods. These unaudited interim condensed consolidated financial statements have been prepared in accordance with GAAP. In the Company's opinion, the accompanying unaudited condensed consolidated financial statements contain all normal and recurring adjustments necessary for a fair statement of the Company’s financial position as of September 30, 2023, its results of operations and equity for the three and nine months ended September 30, 2023 and 2022 and its cash flows for the nine months ended September 30, 2023 and 2022. The results for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023. The Condensed Consolidated Balance Sheet as of December 31, 2022 was derived from the Company's audited financial statements included in its Annual Report on Form 10-K filed with the SEC on March 8, 2023, but is presented as condensed and does not contain all of the footnote disclosures from the annual financial statements. Recently Adopted Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments, which introduced an expected credit loss methodology for the measurement and recognition of credit losses on most financial instruments, including trade receivables and off-balance sheet credit exposure. Under this guidance, an entity is required to consider a broader range of information to estimate expected credit losses, which may result in earlier recognition of losses. This ASU also requires disclosure of information regarding how a company developed its allowance, including changes in the factors that influenced management’s estimate of expected credit losses and the reasons for those changes. The Company adopted ASU 2016-13 on January 1, 2023 using the modified retrospective method, whereby the guidance was applied prospectively as of the date of adoption and prior periods are not restated. The adoption of this ASU did not have a material impact on the Company's financial position or results of operations. The Company assessed the scope of its financial assets and determined that the guidance associated with ASU 2016-13 is relevant to its trade accounts receivable and contract assets, including retainage. The Company’s trade receivables include amounts from work completed in which it has billed or has an unconditional right to bill its customers. The majority of the Company’s trade receivables are contractually due in less than a year. The Company further assessed the guidance based on its segment portfolio of receivables. While the Company’s construction-type GCR and ODR financial assets are often in the same subset of customers and industries, the Company’s construction-type related project work is typically bonded and the customers to which they perform work are well-known, solvent and have no history of material receivable write-offs. On the contrary, the Company’s service-type work, in particular its ODR core service work, is smaller in nature and is usually more susceptible to customer write-offs. As such, there is greater risk of credit loss on the Company’s ODR-related service-type receivables. The Company’s contract assets include amounts due under retainage provisions and costs and estimated earnings in excess of billings on uncompleted contracts. The Company has policies and procedures in place where it reviews claims and change orders on a quarterly basis to determine legal entitlement and recoverability in accordance with ASC Topic 606. As such, the Company has determined the risk of credit loss on its contracts assets to be remote. The Company develops its allowances for credit losses, which represent an estimate of expected losses over the remaining contractual life of its ODR-related service-type receivables, using an aging method. Under the aging method, the Company assigns its accounts receivable to a level of delinquency and applies a loss rate to each class. Loss rates are determined based on historical loss experiences with customers, the consideration of a customer’s financial condition, current market economic conditions and a forecast of future economic conditions when appropriate. When the Company becomes aware of a customer's inability to meet its financial obligation, a specific reserve is recorded to reduce the receivable to the expected amount to be collected. As part of the Company’s analysis of expected credit losses, it may analyze receivables with customers on an individual basis in situations where such accounts receivables exhibit unique risk characteristics and are not expected to experience similar losses to the rest of their class. Recent Accounting Pronouncements The FASB has issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting in March 2020. This new guidance provides optional expedients for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform, on financial reporting. The risk of termination of the London Interbank Offered Rate (LIBOR), has caused regulators to undertake reference rate reform initiatives to identify alternative reference rates that are more observable or transaction based that are less susceptible to manipulation. ASU 2020-04 was effective between March 12, 2020 and December 31, 2022. However, in December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, extending the sunset date under Topic 848 from December 31, 2022 to December 31, 2024 to align the temporary accounting relief guidance with the expected LIBOR cessation date of June 30, 2023. In addition, in January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848): Scope. The amendments in this update refine the scope for certain optional expedients and exceptions for contract modifications and hedge accounting to apply to derivative contracts and certain hedging relationships affected by the discounting transition. As a result of ASU 2022-06, an entity may now elect to apply the amendments in this update from the beginning of an interim period beginning as of March 12, 2020, through December 31, 2024. The Company has evaluated the impact of adopting the reference rate reform guidance (both ASU 2020-04 and ASU 2021-01) on its consolidated financial statements and has determined that these pronouncements did not have a significant impact. As discussed in Note 6, the A&R Credit Agreement removed LIBOR as a benchmark rate and now utilizes SOFR (as defined in the A&R Credit Agreement) as its replacement. During the second quarter of 2023, the Company entered into the Second A&R Credit Agreement (as defined in Note 6), which also utilizes SOFR as a benchmark rate. In addition, the Company’s interest rate swap utilizes SOFR as its benchmark rate. In August 2020, the FASB issued ASU 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity, which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity and amends the scope guidance for contracts in an entity's own equity. The ASU addresses how convertible instruments are accounted for in the calculation of diluted earnings per share by using the if-converted method. The guidance is effective for all entities for fiscal years beginning after March 31, 2024, albeit early adoption is permitted no earlier than fiscal years beginning after December 15, 2020. Management is currently assessing the impact of this pronouncement on its condensed consolidated financial statements.

v3.23.3

Acquisitions	9 Months Ended
	Sep. 30, 2023
Business Combination and Asset Acquisition [Abstract]
Acquisitions	Acquisitions ACME Transaction On July 3, 2023 (the “Effective Date”), the Company, LFS and ACME (the “Acquired Company”), and the owner of the Acquired Company (the “Seller”) entered into a Purchase Agreement (the “Purchase Agreement”) pursuant to which LFS purchased all of the outstanding equity interests in the Acquired Company from the Seller (the “ACME Transaction”). The ACME Transaction closed on the Effective Date. As a result of the ACME Transaction, the Acquired Company became a wholly-owned indirect subsidiary of the Company. ACME specializes in performing industrial maintenance, capital project work, and emergency services for specialty chemical and manufacturing clients, and is a leading mechanical solutions provider for hydroelectric producers. The acquisition expands the Company’s market share within its existing operating footprint, provides further exposure to an attractive customer base and supports the Company's continued ODR growth strategy. Total consideration paid by the Company for the ACME Transaction at closing was $5.0 million (the “Closing Purchase Price”), consisting of cash paid to the Seller, subject to typical adjustments for working capital. Of the consideration paid to the Seller, approximately $0.4 million is being held in escrow for indemnification purposes. The purchase price is subject to customary post-closing adjustments. In addition, the Seller may receive up to an aggregate of $2.5 million in cash, consisting of two individual tranches of $0.5 million and $2.0 million pursuant to the terms of the Purchase Agreement, if the gross profit of the Acquired Company equals or exceeds (i) $2.0 million in the 12-month period beginning on the Effective Date (the “First ACME Earnout Period”) or (ii) $2.5 million in the 12-month period beginning on the first anniversary of the Effective Date (the “Second ACME Earnout Period” and together with the First ACME Earnout Period, the “ACME Earnout Payments”). The Company recorded $0.3 million in acquisition-related expenses associated with professional fees related to the ACME Transaction during the three and nine months ending September 30, 2023, which are included in selling, general and administrative expense in the condensed consolidated statement of operations. Allocation of Purchase Price. The ACME Transaction was accounted for as a business combination using the acquisition method. The following table summarizes the preliminary purchase price and estimated fair values of assets acquired and liabilities assumed as of the Effective Date, with any excess of purchase price over estimated fair value of the identified net assets acquired recorded as goodwill. As a result of the acquisition, the Company recognized $2.3 million of goodwill, all of which was allocated to the ODR segment and fully deductible for tax purposes. Such goodwill primarily related to anticipated future earnings. The following table summarizes the preliminary allocation of the fair value of the assets and liabilities of the ACME Transaction as of the Effective Date by the Company. (in thousands) Purchase Price Allocation Consideration: Cash $ 5,181  Earnout provision 1,121  Total Consideration 6,302  Fair value of assets acquired: Cash and cash equivalents 298  Accounts receivable 1,150  Contract assets 414  Property and equipment 488  Operating lease right-of-use assets 301  Intangible assets 2,300  Amount attributable to assets acquired 4,951  Fair value of liabilities assumed: Accounts payable, including retainage 170  Current operating lease liabilities 195  Accrued expenses and other current liabilities 138  Contract liabilities 373  Long-term operating lease liabilities 106  Amount attributable to liabilities assumed 982  Goodwill $ 2,333  For working capital items, such as cash and cash equivalents, accounts receivable, other current assets, accounts payable and accrued expenses and other current liabilities, the Acquired Company's carrying value was assumed to represent the fair value of these assets due to the current nature of the assets and liabilities. There was no difference between the contract value and fair value of accounts receivable acquired. The estimated fair value of property and equipment, generally consisting of vehicles, machinery, and equipment, was estimated using the cost approach. Significant unobservable inputs in the estimate of fair value under this approach included management's assumptions about the replacement costs for similar assets, the relative age of the acquired assets and any potential economic or functional obsolescence associated with the acquired assets. As a result, the estimated fair value of the property and equipment represented a Level 3 fair value measurement. As part of the purchase price allocation, the Company identified certain definite-lived intangible assets associated with customer relationships with third-party customers and the acquired trade name and trademarks. The fair value of the customer relationships with third-party customers was determined using the multi-period excess earning method under the income approach. The multi-period excess earnings method is a variation of the discounted cash-flow analysis, which isolates the cash flows that can be associated with a single intangible asset and measures fair value by discounting it back to present value. The fair value of the acquired trade name and trademarks intangible asset was determined using an income approach, specifically known as the relief-from-royalty method. This method requires identifying the future revenue that would be generated by the trademark, multiplying it by a royalty rate deemed to be avoided through ownership of the asset and discounting the projected royalty savings amounts back to the acquisition date. The royalty rate used in the valuation was based on a consideration of market rates for similar categories of assets. Some of the more significant estimates and assumptions inherent in determining the fair value of the identifiable intangible assets are associated with forecasting cash flows and profitability, which represent Level 3 inputs. The Company calculates amortization of the acquired intangible assets using the straight-line method over the estimated useful lives of each acquired intangible assets. Amortization expense recorded in the consolidated statements of operations for the period from the Effective Date to September 30, 2023 was approximately $0.1 million. The estimated annual amortization expense for the remainder of 2023 is approximately $0.1 million, and $0.3 million for each of the next five years. Intangible assets, net as of September 30, 2023 are detailed below. (in thousands) Gross Carrying Amount Accumulated Amortization Net Intangible Assets Weighted Average Useful Life (Years) Trade name and trademarks $ 400 $ (18) $ 382 5.5 Customer relationships 1,900 (46) 1,854 10.3 Total $ 2,300 $ (64) $ 2,236 6.3 The aforementioned contingent ACME Earnout Payments are associated with the achievement of specified gross profit milestones. The Company estimated that the fair value of the ACME Earnout Payments was approximately $1.1 million at the date of acquisition, of which the majority of this balance was included in other long-term liabilities in the Company’s consolidated balance sheet as of September 30, 2023. The Company determined the initial fair value of the ACME Earnout Payments based on the Monte Carlo Simulation method, which represented a Level 3 measurement. As of the Effective Date, the ACME Earnout Payments associated with the ACME Transaction were valued utilizing discount rates of 8.65% and 14.49%. The discount rates were calculated using the build-up method with a risk-free rate commensurate with the term of the ACME Earnout Payments based on the U.S. Treasury Constant Maturity Yield and certain metric risk premiums determined with reference to a long-term risk free rate, a weighted average cost of capital and certain adjustments for operational leverage. Subsequent to the Effective Date, the ACME Earnout Payments are re-measured at fair value each reporting period. Changes in the estimated fair value of the contingent payments subsequent to the acquisition date are recognized immediately in earnings.

v3.23.3

Revenue from Contracts with Customers	9 Months Ended
	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers The Company generates revenue from construction type contracts, primarily consisting of fixed-price contracts, to deliver HVAC, plumbing, and electrical construction services to its customers. The duration of its contracts generally ranges from three months to two years. Revenue from fixed price contracts is recognized on the cost-to-cost method, measured by the relationship of total cost incurred to total estimated contract costs. Revenue from time and materials contracts is recognized as services are performed. The Company believes that its extensive experience in HVAC, plumbing, and electrical projects, and its internal cost review procedures during the bidding process, enable it to reasonably estimate costs and mitigate the risk of cost overruns on fixed price contracts. The Company generally invoices customers on a monthly basis, based on a schedule of values that breaks down the contract amount into discrete billing items. Costs and estimated earnings in excess of billings on uncompleted contracts are recorded as a contract asset until billable under the contract terms. Billings in excess of costs and estimated earnings on uncompleted contracts are recorded as a contract liability until the related revenue is recognizable. The Company classifies contract assets and liabilities that may be settled beyond one year from the balance sheet date as current, consistent with the length of time of the Company’s project operating cycle. Contract assets Contract assets include amounts due under retainage provisions and costs and estimated earnings in excess of billings on uncompleted contracts. The components of the contract asset balances as of the respective dates were as follows: (in thousands) September 30, 2023 December 31, 2022 Change Contract assets Costs and estimated earnings in excess of billings on uncompleted contracts $ 26,007  $ 33,573  $ (7,566) Retainage receivable 21,846  27,880  (6,034)       Total contract assets $ 47,853  $ 61,453  $ (13,600) Retainage receivable represents amounts invoiced to customers where payments have been partially withheld, typically 10%, pending the completion of certain milestones, satisfaction of other contractual conditions or the completion of the project. Retainage agreements vary from project to project and balances could be outstanding for several months or years depending on a number of circumstances such as contract-specific terms, project performance and other variables that may arise as the Company makes progress towards completion. Contract assets represent the excess of contract costs and profits (or contract revenue) over the amount of contract billings to date and are classified as a current asset. Contract assets result when either: (1) the appropriate contract revenue amount has been recognized over time in accordance with ASC Topic 606, but a portion of the revenue recorded cannot be currently billed due to the billing terms defined in the contract, or (2) costs are incurred related to certain claims and unapproved change orders. Claims occur when there is a dispute regarding both a change in the scope of work and the price associated with that change. Unapproved change orders occur when a change in the scope of work results in additional work being performed before the parties have agreed on the corresponding change in the contract price. The Company routinely estimates recovery related to claims and unapproved change orders as a form of variable consideration at the most likely amount it expects to receive and to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. Claims and unapproved change orders are billable upon the agreement and resolution between the contractual parties and after the execution of contractual amendments. Increases in claims and unapproved change orders typically result from costs being incurred against existing or new positions; decreases normally result from resolutions and subsequent billings. The current estimated net realizable value on such items as recorded in contract assets and contract liabilities in the condensed consolidated balance sheets was $19.7 million and $28.5 million as of September 30, 2023 and December 31, 2022, respectively. The Company currently anticipates that the majority of such amounts will be approved or executed within one year. The resolution of those claims and unapproved change orders that may require litigation or other forms of dispute resolution proceedings may delay the timing of billing beyond one year. Contract liabilities Contract liabilities include billings in excess of contract costs and provisions for losses. The components of the contract liability balances as of the respective dates were as follows: (in thousands) September 30, 2023 December 31, 2022 Change Contract liabilities Billings in excess of costs and estimated earnings on uncompleted contracts $ 46,545  $ 43,806  $ 2,739  Provisions for losses 147  201  (54)       Total contract liabilities $ 46,692  $ 44,007  $ 2,685  Billings in excess of costs and estimated earnings on uncompleted contracts represent the excess of contract billings to date over the amount of contract costs and profits (or contract revenue) recognized to date. The balance may fluctuate depending on the timing of contract billings and the recognition of contract revenue. Provisions for losses are recognized in the condensed consolidated statements of operations at the uncompleted performance obligation level for the amount of total estimated losses in the period that evidence indicates that the estimated total cost of a performance obligation exceeds its estimated total revenue. The net (overbilling) underbilling position for contracts in process consisted of the following: (in thousands) September 30, 2023 December 31, 2022 Revenue earned on uncompleted contracts $ 625,765  $ 678,014  Less: Billings to date (646,303) (688,247)    Net (overbilling) underbilling $ (20,538) $ (10,233) (in thousands) September 30, 2023 December 31, 2022 Costs in excess of billings and estimated earnings on uncompleted contracts $ 26,007  $ 33,573  Billings in excess of costs and estimated earnings on uncompleted contracts (46,545) (43,806)    Net (overbilling) underbilling $ (20,538) $ (10,233) Revisions in Contract Estimates The Company recorded revisions in its contract estimates for certain GCR and ODR projects. During the three months ended September 30, 2023, the Company recorded material gross profit write-ups on three GCR projects for a total of $3.1 million, inclusive of a $1.2 million write-up related to the settlement of a past claim, and one material GCR project gross profit write-down for $0.7 million and one material ODR project gross profit write-down for $0.6 million. During the nine months ended September 30, 2023, the Company recorded material gross profit write-ups on two GCR projects for a total of $2.2 million, inclusive of a $1.2 million write-up related to the settlement of a past claim, and one material GCR project gross profit write-down for $0.5 million and one material ODR project gross profit write-down for $0.7 million. During the three months ended September 30, 2022, the Company did not record any material gross profit write-ups or write-downs that had a net gross profit impact of $0.5 million or more. During the nine months ended September 30, 2022, the Company recorded material gross profit write-ups on two GCR projects for a total of $2.0 million and two material GCR project gross profit write-downs for a total of $1.1 million. Remaining Performance Obligations Remaining performance obligations represent the transaction price of firm orders for which work has not been performed and exclude unexercised contract options. The Company’s remaining performance obligations include projects that have a written award, a letter of intent, a notice to proceed or an agreed upon work order to perform work on mutually accepted terms and conditions. As of September 30, 2023, the aggregate amount of the transaction prices allocated to the remaining performance obligations of the Company's GCR and ODR segment contracts were $227.0 million and $138.1 million, respectively. The Company currently estimates that 27% and 48% of its GCR and ODR remaining performance obligations as of September 30, 2023, respectively, will be recognized as revenue during the remainder of 2023, with the substantial majority of remaining performance obligations to be recognized within 24 months, although the timing of the Company's performance is not always under its control. Additionally, the difference between remaining performance obligations and backlog is due to the exclusion of a portion of the Company’s ODR agreements under certain contract types from the Company’s remaining performance obligations as these contracts can be canceled for convenience at any time by the Company or the customer without considerable cost incurred by the customer.

v3.23.3

Goodwill and Intangibles	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangibles	Goodwill and Intangibles Goodwill Goodwill was $13.7 million and $11.4 million as of September 30, 2023 and December 31, 2022, respectively, and is entirely associated with the Company's ODR segment. The Company tests its goodwill and indefinite-lived intangible assets allocated to its reporting units for impairment annually on October 1, or more frequently if events or circumstances indicate that it is more likely than not that the fair value of its reporting units and indefinite-lived intangible assets are less than their carrying amount. The Company has the option to assess goodwill for possible impairment by performing a qualitative analysis to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. A quantitative assessment is performed if the qualitative assessments results in a more-likely-than-not determination or if a qualitative assessment is not performed. The Company did not recognize any impairment charges on its goodwill or intangible assets during the three and nine months ended September 30, 2023 and September 30, 2022. The following table summarizes the carrying amount and changes in goodwill associated with the Company's segments for the nine months ended September 30, 2022 and for the year ended December 31, 2022. (in thousands) GCR ODR Total Goodwill as of January 1, 2022 $ —  $ 11,370  $ 11,370  Goodwill as of December 31, 2022 —  11,370  11,370  Goodwill associated with the ACME Transaction —  2,333  2,333  Goodwill as of September 30, 2023 $ —  $ 13,703  $ 13,703  Intangible Assets Intangible assets are comprised of the following:      (in thousands) Gross carrying amount Accumulated amortization Net intangible assets, excluding goodwill September 30, 2023 Amortized intangible assets: Customer relationships – GCR – Jake Marshall $ 570  $ (148) $ 422  Customer relationships – ODR – Jake Marshall 3,050  (737) 2,313  Customer relationships – ODR – ACME 1,900  (46) 1,854  Customer relationships – ODR – Limbach 4,710  (3,944) 766  Favorable leasehold interests – Limbach 190  (109) 81  Backlog – GCR – Jake Marshall 260  (260) —  Backlog – ODR – Jake Marshall 680  (680) —  Trade name – Jake Marshall 1,150  (342) 808  Trade name – ACME 400  (18) 382  Total amortized intangible assets 12,910  (6,284) 6,626  Unamortized intangible assets: Trade name – Limbach(1) 9,960  —  9,960  Total unamortized intangible assets 9,960  —  9,960  Total amortized and unamortized assets, excluding goodwill $ 22,870  $ (6,284) $ 16,586  (1)    The Company has determined that its trade name has an indefinite useful life. The Limbach trade name has been in existence since the Company’s founding in 1901 and therefore is an established brand within the industry. (in thousands) Gross carrying amount Accumulated amortization Net intangible assets, excluding goodwill December 31, 2022       Amortized intangible assets:       Customer relationships – GCR – Jake Marshall $ 570  $ (87) $ 483  Customer relationships – ODR – Jake Marshall 3,050  (436) 2,614  Customer relationships – ODR – Limbach 4,710  (3,765) 945  Favorable leasehold interests – Limbach 190  (97) 93  Backlog – GCR – Jake Marshall 260  (178) 82  Backlog – ODR – Jake Marshall 680  (465) 215  Trade name – Jake Marshall 1,150  (202) 948  Total amortized intangible assets 10,610  (5,230) 5,380  Unamortized intangible assets: Trade name – Limbach 9,960  —  9,960  Total unamortized intangible assets 9,960  —  9,960  Total amortized and unamortized assets, excluding goodwill $ 20,570  $ (5,230) $ 15,340  Total amortization expense for the Company's definite-lived intangible assets was $0.3 million and $0.4 million for the three months ended September 30, 2023 and 2022, respectively, and $1.1 million and $1.2 million for the nine months ended September 30, 2023 and 2022, respectively

v3.23.3

Debt	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Debt	Debt Long-term debt consists of the following obligations as of: (in thousands) September 30, 2023 December 31, 2022 A&R Wintrust Term Loan - term loan payable in quarterly installments of principal, plus interest through February 2026 —  21,453  Wintrust Revolving Loans 10,000  —  Finance leases – collateralized by vehicles, payable in monthly installments of principal, plus interest ranging from 3.96% to 8.60% through 2027 6,949  4,954  Financing liability 5,351  5,351  Total debt 22,300  31,758  Less - Current portion of long-term debt (2,472) (9,564) Less - Unamortized discount and debt issuance costs (391) (666) Long-term debt $ 19,437  $ 21,528  Wintrust Term and Revolving Loans On February 24, 2021, LFS, LHLLC and the direct and indirect subsidiaries of LFS from time to time included as parties to the agreement (the “Wintrust Guarantors”) entered into a credit agreement (the “Wintrust Credit Agreement”) by and among LFS, LHLLC, Wintrust Guarantors, the lenders party thereto from time to time, Wheaton Bank & Trust Company, N.A., a subsidiary of Wintrust Financial Corporation (collectively, “Wintrust”), as administrative agent and L/C issuer, Bank of the West as documentation agent, M&T Bank as syndication agent, and Wintrust as lead arranger and sole book runner. In accordance with the terms of the Wintrust Credit Agreement, Lenders provided to LFS (i) a $30.0 million senior secured term loan (the “Wintrust Term Loan”); and (ii) a $25.0 million senior secured revolving credit facility with a $5.0 million sublimit for the issuance of letters of credit (the “Wintrust Revolving Loan” and, together with the Wintrust Term Loan, the “Wintrust Loans”). Proceeds of the Wintrust Loans were used to refinance certain existing indebtedness, finance working capital and other general corporate purposes and fund certain fees and expenses associated with the closing of the Wintrust Loans. The Wintrust Revolving Loan initially bore interest, at LFS’s option, at either LIBOR (with a 0.25% floor) plus 3.5% or a base rate (with a 3.0% floor) plus 0.50%, subject to a 50 basis point step-down based on the ratio between the senior debt of the Company and its subsidiaries to the EBITDA (earnings before interest, income taxes, depreciation and amortization) of LFS and its subsidiaries for the most recently ended four fiscal quarters. The Wintrust Term Loan initially bore interest, at LFS’s option, at either LIBOR (with a 0.25% floor) plus 4.0% or a base rate (with a 3.0% floor) plus 1.00%, subject to a 50 (for LIBOR) or 75 (for base rate) basis point step-down based on the Senior Leverage Ratio (as defined below). LFS was initially required to make principal payments on the Wintrust Term Loan in $0.5 million installments on the last business day of each month commencing on March 31, 2021 with a final payment of all principal and interest not sooner paid on the Wintrust Term Loan due and payable on February 24, 2026. In conjunction with the Company's acquisitions of JMLLC and CSLLC (the “Jake Marshall Transaction”), the Company entered into an amendment to the Wintrust Credit Agreement (the “A&R Wintrust Credit Agreement”). In accordance with the terms of the A&R Credit Agreement, Lenders provided to LFS (i) a $35.5 million senior secured term loan (the “A&R Wintrust Term Loan”); and (ii) a $25 million senior secured revolving credit facility with a $5 million sublimit for the issuance of letters of credit (the “A&R Wintrust Revolving Loan” and, together with the Term Loan, the “A&R Wintrust Loans”). The overall Wintrust Term Loan commitment under the A&R Wintrust Credit Agreement was recast at $35.5 million in connection with the A&R Credit Agreement. A portion of the A&R Wintrust Term Loan commitment was used to fund the closing purchase price of the Jake Marshall Transaction. The A&R Credit Agreement was also amended to: (i) permit the Company to undertake the Jake Marshall Transaction, (ii) make certain adjustments to the covenants under the A&R Credit Agreement (which were largely done to make certain adjustments for the Jake Marshall Transaction), (iii) allow for the Earnout Payments (as defined in Note 8) under the Jake Marshall Transaction, and (iv) make other corresponding changes to the A&R Credit Agreement. The A&R Wintrust Revolving Loan bore interest, at LFS’s option, at either the Term SOFR (as defined in the A&R Credit Agreement) (with a 0.15% floor) plus 3.60%, 3.76% or 3.92% for a tenor of one month, three months or six months, respectively, or a base rate (as set forth in the A&R Credit Agreement) (with a 3.0% floor) plus 0.50%, subject to a 50 basis point step-down based on the ratio between the senior debt of the Company and its subsidiaries to the EBITDA of LFS and its subsidiaries for the most recently ended four fiscal quarters (the “Senior Leverage Ratio”). The A&R Wintrust Term Loan bore interest, at LFS’s option, at either Term SOFR (with a 0.15% floor) plus 4.10%, 4.26% or 4.42% for a tenor of one month, three months or six months, respectively, or a base rate (with a 3.0% floor) plus 1.00%, subject to a 50 (for Term SOFR) or 75 (for base rate) basis point step-down based on the Senior Leverage Ratio. The A&R Wintrust Term Loan was payable through a combination of (i) monthly installments of approximately $0.6 million due on the last business day of each month commencing on December 31, 2021, (ii) annual Excess Cash Flow payments as defined in the A&R Wintrust Credit Agreement, which are due 120 days after the last day of the Company's fiscal year and (iii) Net Claim Proceeds from Legacy Claims as defined in the A&R Wintrust Credit Agreement. Subject to defaults and remedies under the A&R Credit Agreement, the final payment of all principal and interest not sooner paid on the A&R Wintrust Term Loan was due and payable on February 24, 2026. Subject to defaults and remedies under the A&R Credit Agreement, the A&R Wintrust Revolving Loan would have matured and become due and payable by LFS on February 24, 2026. During the second quarter of 2022, the Company made certain Excess Cash Flow and Net Claim Proceeds payments of $3.3 million and $2.1 million, respectively, which concurrently reduced the outstanding A&R Wintrust Term Loan balance. In addition, during the third quarter of 2022, the Company made a Net Claim Proceeds payment of $0.6 million, which was also applied against the outstanding A&R Wintrust Term Loan balance. The A&R Wintrust Loans were secured by (i) a valid, perfected and enforceable lien of the administrative agent on the ownership interests held by each of LFS and Wintrust Guarantors in their respective subsidiaries; and (ii) a valid, perfected and enforceable lien of the administrative agent on each of LFS and Wintrust Guarantors’ personal property, fixtures and real estate, subject to certain exceptions and limitations. Additionally, the re-payment of the A&R Wintrust Loans shall be jointly and severally guaranteed by each Wintrust Guarantor. The A&R Credit Agreement contained representations and warranties, covenants and events of default that are customary for facilities of this type, as more particularly described in the A&R Credit Agreement. The A&R Wintrust Loans also contain three financial maintenance covenants, including (i) a requirement to have as of the last day of each quarter for the senior leverage ratio of the Company and its subsidiaries not to exceed an amount beginning at 2.00 to 1.00, (ii) a fixed charge coverage ratio of not less than 1.20 to 1.00 as of the last day of each fiscal quarter, commencing with the fiscal quarter ending December 31, 2021, and (iii) no unfinanced capital expenditures, except for unfinanced capital expenditures in the ordinary course of business not exceeding in the aggregate $4.0 million during any fiscal year; and no default or event of default (as defined by the agreement) has occurred and is continuing, 50% of any portion of this annual limit, if not expended in the fiscal year for which it is permitted, may be carried over for expenditure in the next following fiscal year as stipulated by the agreement. LFS and its affiliates maintain various commercial and service relationships with certain members of the syndicate and their affiliates in the ordinary course of business. On May 5, 2022, the Company, LFS and LHLLC entered into a first amendment and waiver to the A&R Wintrust Credit Agreement (the “First Amendment to the A&R Wintrust Credit Agreement”) with the lenders party thereto and Wintrust, as administrative agent. The First Amendment to the A&R Wintrust Credit Agreement modifies certain definitions within the A&R Wintrust Credit Agreement, and make other corresponding changes, including: (i) the definition of “EBITDA” to allow for the recognition of certain restructuring charges and lease breakage costs not previously specified, (ii) the definition of “Excess Cash Flow” to exclude the aggregate amount of the Earnout Payments paid in cash, (iii) the definition of “Total Funded Debt” to exclude certain capitalized lease obligations for real estate based on the approval of each lender and (iv) the definition of “Disposition” to include a clause for the sale and leaseback of certain real property based on the approval of each lender. In July 2022, the Company entered into an interest rate swap agreement to manage the risk associated with a portion of its variable-rate long-term debt. The interest rate swap involves the exchange of fixed-rate and variable-rate payments without the exchange of the underlying notional amount on which the interest payments are calculated. The new swap agreement became effective on July 14, 2022 and will terminate on July 31, 2027. The notional amount of the swap agreement is $10.0 million with a fixed interest rate of 3.12%. If the one-month SOFR (as defined in the A&R Credit Agreement) is above the fixed rate, the counterparty pays the Company, and if the one-month SOFR is less than the fixed rate, the Company pays the counterparty, the difference between the fixed rate of 3.12% and one-month SOFR. The Company has not designated this instrument as a hedge for accounting purposes. As a result, the change in fair value of the derivative instrument is recognized directly in earnings on the Company's condensed consolidated statements of operations as a gain or loss on interest rate swap. Refer to Note 8 for further information regarding this interest rate swap. On September 28, 2022, the Company, LFS and LHLLC entered into a second amendment and waiver to the amended and restated Wintrust credit agreement (the “Second Amendment to the A&R Wintrust Credit Agreement”) with the lenders party thereto and Wintrust, as administrative agent. The Second Amendment to the A&R Wintrust Credit Agreement incorporates certain restricted payment provisions, among other things, to permit LFS to repurchase shares under the Company’s Share Repurchase Program (as defined in Note 7). On May 5, 2023, LFS, LHLLC and the direct and indirect subsidiaries of LFS from time to time included as parties to the agreement entered into the Second Amended and Restated Credit Agreement (the “Second A&R Credit Agreement”) with the lenders party thereto and Wintrust, as administrative agent, which amends and restates the A&R Wintrust Credit Agreement. In accordance with the Second A&R Credit Agreement (i) lenders provided to LFS a $50.0 million senior secured revolving credit facility with a $5.0 million sublimit for the issuance of letters of credit, an increase of $25.0 million over the A&R Wintrust Revolving Loan, with a maturity date of February 24, 2028 (the “Second A&R Wintrust Revolving Loan”), and (ii) LFS repaid the then outstanding principal balance of the A&R Wintrust Term Loan using proceeds of the Second A&R Wintrust Revolving Loan. Prior to the execution of this agreement, the Company repaid $9.6 million of the then outstanding balance under the A&R Term Loan with cash on hand. As a result of the early repayment of the A&R Wintrust Term Loan and certain changes to the members of the loan syndicate under the Second A&R Wintrust Credit Agreement, the Company wrote off approximately $0.3 million of unamortized debt issuance costs, which are reported as a loss on early debt extinguishment on the Company's condensed consolidated statements of operations. Prior to its repayment on May 5, 2023 and as of September 30, 2022, the interest rate in effect on the non-hedged portion of the A&R Wintrust Term Loan was 9.25% and 7.25%, respectively. For the period from January 1, 2023 through May 5, 2023, the Company incurred interest on the A&R Wintrust Term Loan at a weighted average annual interest rate of 8.76%. For the three and nine months ended September 30, 2022, the Company incurred interest on the A&R Wintrust Term Loan at a weighted average annual interest rate of 6.35% and 5.08%, respectively. The Second A&R Wintrust Revolving Loan bears interest, at LFS’s option, at either the Term SOFR (as defined in the Second A&R Credit Agreement) (with a 0.15% floor) plus 3.10% or the Prime Rate (as defined in the Second A&R Credit Agreement) (with a 3.0% floor), subject to a 50 basis point step-down based on the ratio between the senior debt of the Company and its subsidiaries to the EBITDA of LFS and its subsidiaries for the most recently ended four fiscal quarters. The Second A&R Wintrust Revolving Loan is secured by (i) a valid, perfected and enforceable lien of the administrative agent on the ownership interests held by each of LFS and Wintrust Guarantors in their respective subsidiaries; and (ii) a valid, perfected and enforceable lien of the administrative agent on each of LFS and Wintrust Guarantors’ personal property, fixtures and real estate, subject to certain exceptions and limitations. Additionally, the re-payment of the Second A&R Wintrust Revolving Loan is jointly and severally guaranteed by each Wintrust Guarantor. The Second A&R Credit Agreement contains representations and warranties, covenants and events of default that are customary for facilities of this type, as more particularly described in the Second A&R Credit Agreement. The Second A&R Wintrust Revolving Loan also contains three financial maintenance covenants, including (i) a requirement to have as of the last day of each quarter for the senior leverage ratio of LFS and its subsidiaries not to exceed an amount beginning at 2.00 to 1.00, (ii) a fixed charge coverage ratio of not less than 1.20 to 1.00 as of the last day of each fiscal quarter, commencing with the fiscal quarter ending March 31, 2023, and (iii) no unfinanced capital expenditures, except for unfinanced capital expenditures in the ordinary course of business not exceeding in the aggregate $4.0 million during any fiscal year; and no default or event of default (as defined in the Second A&R Credit Agreement) has occurred and is continuing, 50% of any portion of this annual limit, if not expended in the fiscal year for which it is permitted, may be carried over for expenditure in the next following fiscal year as stipulated by the agreement. As of September 30, 2023, the Company had $10.0 million in borrowings outstanding under the Second A&R Wintrust Revolving Loan. As of December 31, 2022, the Company had no borrowings outstanding under the A&R Wintrust Revolving Loan. During the three and nine months ended September 30, 2023, the maximum outstanding borrowings under either the Company's revolving loan arrangements at any time was $10.0 million during both periods and the average daily balance was approximately $10.0 million and $5.5 million, respectively. For the three and nine months ended September 30, 2023, the Company incurred interest on the Second A&R Wintrust Revolving Loan at a weighted average annual interest rate of 5.72% during both periods, inclusive of the net impact associated with the Company's interest rate swap arrangement. During the three and nine months ended September 30, 2022, the maximum outstanding borrowings under the A&R Wintrust Revolving Loan at any time was $3.5 million and $9.4 million, respectively, and the average daily balance was approximately $0.2 million and $0.1 million, respectively. For the three and nine months ended September 30, 2022, the Company incurred interest on the A&R Wintrust Revolving Loan at a weighted average annual interest rate of 5.25% and 4.78%, respectively. At September 30, 2023, the Company had irrevocable letters of credit in the amount of $4.2 million with its lender to secure obligations under its self-insurance program. The following is a summary of the applicable margin and commitment fees payable on the Second A&R Wintrust Revolving Loan credit commitment: Level Senior Leverage Ratio Applicable Margin for SOFR Revolver loans Applicable Margin for Prime Revolving loans Applicable Margin for commitment fee I Greater than 1.00 to 1.00 3.10  % —  % 0.25  % II Less than or equal to 1.00 to 1.00 2.60  % (0.50) % 0.25  % As of September 30, 2023, the Company was in compliance with all financial maintenance covenants as required by the A&R Wintrust Loans. Sale-Leaseback Financing Transaction On September 29, 2022, LC LLC and Royal Oak Acquisitions, LLC (the “Purchaser”) consummated the purchase of the real property under a sale and leaseback transaction, with an aggregate value of approximately $7.8 million (a purchase price of approximately $5.4 million and $2.4 million in tenant improvement allowances), pursuant to a purchase agreement under which the Purchaser purchased from LC LLC the Company’s facility and real property in Pontiac, MI (collectively, the “Pontiac Facility”). In connection with the sale and leaseback transaction, LC LLC and Featherstone St Pontiac MI LLC (the “Landlord”) entered into a Lease Agreement (the “Lease Agreement”), dated September 29, 2022 (the “Lease Effective Date”) for the Pontiac Facility. Commencing on the Lease Effective Date, pursuant to the Lease Agreement, LC LLC has leased the Pontiac Facility, subject to the terms and conditions of the Lease Agreement. The Lease Agreement provides for a term of 25 years (the “Primary Term”). The Lease Agreement also provides LC LLC with the option to extend the Primary Term by two separate renewal terms of five years each (each a “Renewal Term”). Under the terms of the Lease Agreement, the Company’s annual minimum rent is $499,730, payable in monthly installments, subject to annual increases of approximately 2.5% each year under the Primary Term and for each year under the Renewal Terms, if exercised. LC LLC has a one-time option to terminate the Lease Agreement effective on the last day of the fifteenth lease year by providing written notice to the Landlord as more fully set forth in the Lease Agreement. The one-time termination option of the Lease Agreement would require LC LLC to pay to the Landlord a termination fee of approximately $1.7 million. Pursuant to the terms and conditions set forth in the Lease Agreement, the Landlord has agreed to provide LC LLC with a tenant improvement allowance in an amount up to $2.4 million. LC LLC is responsible for the initial capital outlay and completion of the agreed upon improvement work. The Landlord will subsequently reimburse LC LLC for such items up to the stated allowance amount. The Company accounted for the sale and leaseback arrangement as a financing transaction in accordance with ASC Topic 842, “Leases,” as the Lease Agreement was determined to be a finance lease. The Company concluded the Lease Agreement met the qualifications to be classified as a finance lease due to the significance of the present value of the lease payments, using an implicit rate of 11.11% to reflect the Company’s incremental borrowing rate associated with the $5.4 million purchase price as of the Lease Agreement date, compared to the fair value of the Pontiac Facility. The implicit rate associated with the aggregate purchase value, inclusive of tenant improvement allowances, was 6.53% as of the Lease Agreement date. The presence of a finance lease indicates that control of the Pontiac Facility has not transferred to the Purchaser and, as such, the transaction was deemed a failed sale-leaseback and must be accounted for as a financing arrangement. As a result of this determination, the Company is viewed as having received the sale proceeds from the Purchaser in the form of a hypothetical loan collateralized by its leased facilities. The hypothetical loan is payable as principal and interest in the form of “lease payments” to the Purchaser. Principal repayments are recorded as a reduction to the financing liability. The Company will not derecognize the Pontiac Facility from its books for accounting purposes until the lease ends. No gain or loss was recognized under GAAP related to the sale and leaseback arrangement. As of September 30, 2023, the financing liability was $4.9 million, net of issuance costs, which was recognized within long-term debt on the Company's condensed consolidated balance sheets. For the three and nine months ended September 30, 2023, approximately $0.1 million and $0.4 million of interest expense associated with the financing was recognized.

v3.23.3

Equity	9 Months Ended
	Sep. 30, 2023
Equity [Abstract]
Equity	EquityThe Company’s second amended and restated certificate of incorporation currently authorizes the issuance of 100,000,000 shares of common stock, par value $0.0001, and 1,000,000 shares of preferred stock, par value $0.0001. Warrants In conjunction with the Company's initial public offering, the Company issued Public Warrants, Private Warrants and $15 Exercise Price Sponsor Warrants. The Company issued certain Merger Warrants and Additional Merger Warrants in conjunction with the Company's business combination with LHLLC in July 2016 (the “Business Combination”). On July 20, 2021, the Public Warrants, Private Warrants, and Additional Merger Warrants expired by their terms. During the three months ended June 30, 2023, 600,000 $15 Exercise Price Sponsor Warrants and 163,444 Merger Warrants were exercised on a cashless basis by the holders of the warrants, which resulted in the warrants being converted into 167,564 and 45,797 shares of the Company's common stock, respectively. For the period from July 1, 2023 through July 20, 2023, the holders of the Merger Warrants exercised 443,032 warrants on a cashless basis, which resulted in the Merger Warrants being converted into 228,945 shares of the Company's common stock. The remaining 23,167 unexercised Merger Warrants expired by their terms on July 20, 2023. The following table summarizes the underlying shares of common stock with respect to outstanding warrants: September 30, 2023 December 31, 2022 $15 Exercise Price Sponsor Warrants(1)(2) —  600,000  Merger Warrants(3)(4) —  629,643     Total —  1,229,643  (1)    Exercisable for one share of common stock at an exercise price of $15.00 per share (“$15 Exercise Price Sponsor Warrants”). (2)    Issued under a warrant agreement dated July 15, 2014, between Continental Stock Transfer and Trust Company, as warrant agent, and the Company. (3)    Exercisable for one share of common stock at an exercise price of $12.50 per share (“Merger Warrants”). (4)    Issued to the sellers of LHLLC. Incentive Plan Upon the consummation of the Company's Business Combination, the Company adopted an omnibus incentive plan (the “Omnibus Incentive Plan”) pursuant to which equity awards may be granted thereunder. On March 25, 2022, the Board of Directors approved certain amendments to the Company's Omnibus Incentive Plan (the “2022 Amended and Restated Omnibus Incentive Plan”) to increase the number of shares of the Company's common stock that may be issued pursuant to awards by 350,000, for a total of 2,600,000 shares, and extended the term of the plan so that it will expire on the tenth anniversary of the date the stockholders approve the 2022 Amended and Restated Omnibus Incentive Plan. The amendments were approved by the Company's stockholders at the Annual Meeting held on June 22, 2022. On March 29, 2023, the Board of Directors approved certain amendments to the Company's Omnibus Incentive Plan (the “2023 Amended and Restated Omnibus Incentive Plan”) to increase the number of shares of the Company's common stock that may be issued pursuant to awards by 450,000, for a total of 3,050,000 shares, and extended the term of the plan so that it will expire on the tenth anniversary of the date the stockholders approve the 2023 Amended and Restated Omnibus Incentive Plan. The amendments were acted upon by the Company's stockholders at the Annual Meeting held on June 22, 2023. See Note 14 for a discussion of the Company's management incentive plans for restricted stock units (“RSUs”) granted, vested, forfeited and remaining unvested. Share Repurchase Program In September 2022, the Company announced that its Board of Directors approved a share repurchase program (the “Share Repurchase Program”) to repurchase shares of its common stock for an aggregate purchase price not to exceed $2.0 million. The share repurchase authority was valid through September 29, 2023. Share repurchases may have been executed through various means, including, without limitation, open market transactions, privately negotiated transactions or by other means in accordance with federal securities laws. The Share Repurchase Program did not obligate the Company to acquire any particular amount of common stock, and the program may have been suspended or terminated by the Company at any time at its discretion without prior notice. As of September 30, 2023, the Company has made share repurchases of approximately $2.0 million under its Share Repurchase Program. Employee Stock Purchase Plan Upon approval of the Company's stockholders on May 30, 2019, the Company adopted the Limbach Holdings, Inc. 2019 Employee Stock Purchase Plan (the “ESPP”). On January 1, 2020, the ESPP went into effect. The ESPP enables eligible employees, as defined by the ESPP, the right to purchase the Company's common stock through payroll deductions during consecutive subscription periods at a purchase price of 85% of the fair market value of a common share at the end of each offering period. Annual purchases by participants are limited to the number of whole shares that can be purchased by an amount equal to ten percent of the participant's compensation or $5,000, whichever is less. Each offering period of the ESPP lasts six months, commencing on January 1 and July 1 of each year. The amounts collected from participants during a subscription period are used on the exercise date to purchase full shares of common stock. Participants may withdraw from an offering before the exercise date and obtain a refund of amounts withheld through payroll deductions. Compensation cost, representing the 15% discount applied to the fair market value of common stock, is recognized on a straight-line basis over the six-month vesting period during which employees perform related services. Under the ESPP, 500,000 shares are authorized to be issued. In January 2023 and July 2023, the Company issued 10,997 and 6,664 shares of its common stock, respectively, to participants in the ESPP who contributed to the plan during the offering periods ending December 31, 2022 and June 30, 2023, respectively. In January 2022 and July 2022, the Company issued a total of 12,898 and 24,592 shares of its common stock, respectively, to participants in the ESPP who contributed to the plan during the offering periods ending December 31, 2021 and June 30, 2022, respectively. As of September 30, 2023, 388,956 shares remain available for future issuance under the ESPP.

v3.23.3

Fair Value Measurements	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company measures the fair value of financial assets and liabilities in accordance with ASC Topic 820 – Fair Value Measurements and Disclosures, which defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements. ASC Topic 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value and requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows: •Level 1 — inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that are accessible at the measurement date; •Level 2 — inputs other than quoted prices included in Level 1 that are observable for the asset or liability either directly or indirectly such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities; and •Level 3 — unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. The Company believes that the carrying amounts of its financial instruments, including cash and cash equivalents, trade accounts receivable and accounts payable, consist primarily of instruments without extended maturities, which approximate fair value primarily due to their short-term maturities and low risk of counterparty default. The Company considers all highly liquid investments purchased with a maturity of 90 days or less on the date of purchase to be cash equivalents. Cash equivalents as of September 30, 2023 consisted of overnight repurchase agreements in which cash from the Company's main operating checking account is invested overnight in highly liquid, short term investments, one U.S. Treasury Bill and certain investments in money market funds sponsored by a large financial institution. The Company had no such investments as of December 31, 2022. For the three and nine months ending September 30, 2023, the Company recognized interest income in the aggregate of approximately $0.4 million and $0.6 million associated with its overnight repurchase agreements, U.S. Treasury Bills and money market funds, respectively. The Company has not experienced any losses in its cash and cash equivalents and management believes the Company is not exposed to significant credit risk with respect to such accounts. Fair Value at Reporting Date Using (in thousands) September 30, 2023 Level 1 Level 2 Level 3 Cash equivalents: Overnight repurchase agreements $ 41,687  $ 41,687  U.S. Treasury Bills 10,000  10,000  $ —  $ —  Money market fund 3,750  3,750  —  —  Total $ 55,437  $ 55,437  $ —  $ —  Second A&R Wintrust Revolving Loan The Company also believes that the carrying value of the Second A&R Wintrust Revolving Loan approximates its respective fair value due to the variable rate on such debt. As of September 30, 2023, the Company determined that the fair value of the Second A&R Wintrust Revolving Loan was $10.0 million. Such fair value was determined using discounted estimated future cash flows using level 3 inputs. Earnout Payments As a part of the total consideration for the Jake Marshall Transaction, the former owners of JMLLC and CSLLC may receive up to an aggregate of $6.0 million in cash, consisting of two tranches of $3.0 million, as defined in the purchase agreement, if the gross profit of the acquired companies equals or exceeds $10.0 million in (i) the approximately 12-month period from closing through December 31, 2022 (the “2022 Jake Marshall Earnout Period”) or (ii) fiscal year 2023 (the “2023 Jake Marshall Earnout Period”), respectively (collectively, the “Jake Marshall Earnout Payments”). To the extent, however, that the gross profit of the acquired companies is less than $10.0 million, but exceeds $8.0 million, during any of the 2022 Jake Marshall Earnout Period or 2023 Jake Marshall Earnout Period, the $3.0 million amount will be prorated for such period. The Company initially recognized $3.1 million in contingent consideration, of which the entire balance was included in other long-term liabilities in the Company’s condensed consolidated balance sheets on December 2, 2021. The fair value of contingent Jake Marshall Earnout Payments is based on generating growth rates on the projected gross margins of the acquired entities and calculating the associated contingent payments based on achieving the earnout targets, which are reassessed each reporting period. In April 2023, the Company made a $3.0 million payment to the former owners of JMLLC and CSLLC related to the 2022 Jake Marshall Earnout Period. Based on the Company’s ongoing assessment of the fair value of contingent earnout liabilities, the Company recorded a net increase in the estimated fair value of such liabilities of $0.2 million and $0.5 million for the three and nine ended September 30, 2023, respectively, which was presented in change in fair value of contingent consideration in the Company's condensed consolidated statements of operations. During the three and nine months ended September 30, 2022, the Company recorded a net increase in the estimated fair value of such liabilities of $0.4 million and $1.2 million, respectively. The Company determined the fair value of the Earnout Payments by utilizing the Monte Carlo Simulation method, which represents a Level 3 measurement. As a part of the total consideration for the ACME Transaction, the Company recognized $1.1 million in contingent consideration on the Effective Date. The fair value of contingent ACME Earnout Payments is based on generating growth rates on the projected gross margins of the Acquired Company and calculating the associated contingent payments based on achieving the earnout targets, which are reassessed each reporting period. The Company determined the initial fair value of the ACME Earnout Payments based on the Monte Carlo Simulation method, which represented a Level 3 measurement. As of the Effective Date, the ACME Earnout Payments associated with the ACME Transaction were valued utilizing discount rates between 8.65% and 14.49%. The discount rates were calculated using the build-up method with a risk-free rate commensurate with the term of the ACME Earnout Payments based on the U.S. Treasury Constant Maturity Yield and certain metric risk premiums determined with reference to a long-term risk free rate, a weighted average cost of capital and certain adjustments for operational leverage. The following table presents the carrying values of the Company's contingent earnout payment obligations included in the accompanying condensed consolidated balance sheets, which approximated fair value at September 30, 2023 and December 31, 2022. Fair Value at Reporting Date Using (in thousands) September 30, 2023 Level 1 Level 2 Level 3 Accrued expenses and other current liabilities: 2023 Jake Marshall Earnout Period $ 2,838  $ —  $ —  $ 2,838  First ACME Earnout Period 12  —  —  12  Other long-term liabilities: Second ACME Earnout Period 1,109  —  —  1,109  Total $ 3,959  $ —  $ —  $ 3,959  Fair Value at Reporting Date Using December 31, 2022 Level 1 Level 2 Level 3 Accrued expenses and other current liabilities: 2022 Jake Marshall Earnout Period (1) $ 2,859  $ —  $ —  $ 2,859  Other long-term liabilities: —  2023 Jake Marshall Earnout Period 2,515  —  —  2,515  Total $ 5,374  $ —  $ —  $ 5,374  (1)    In April 2023, the Company made a $3.0 million payment to the former owners of JMLLC and CSLLC related to the 2022 Jake Marshall Earnout Period. Interest Rate Swap The fair value of the interest rate swap is determined using widely accepted valuation techniques and reflects the contractual terms of the interest rate swap including the period to maturity, and while there are no quoted prices in active markets, it uses observable market-based inputs, including interest rate curves and implied volatilities. The fair value analysis also considers a credit valuation adjustment to reflect nonperformance risk of both the Company and the single counterparty. The fair value of the interest rate contract has been determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The interest rate swap is classified as a Level 2 item within the fair value hierarchy. As of September 30, 2023, the Company determined that the fair value of the interest rate swap was approximately $0.5 million and is recognized in other assets on the Company's condensed consolidated balance sheets. For the three and nine months ended September 30, 2023, the Company recognized a gain of approximately $0.1 million and $0.2 million, respectively, on its condensed consolidated statements of operations associated with the change in fair value of the interest rate swap arrangement. For both the three and nine months ended September 30, 2022, the Company recognized a gain of $0.3 million on its condensed consolidated statements of operations associated with the change in fair value of the interest rate swap arrangement.

v3.23.3

Earnings per Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Earnings per Share	Earnings per Share Earnings per Share The Company calculates earnings per share in accordance with ASC Topic 260 - Earnings Per Share (“EPS”). Basic earnings per common share applicable to common stockholders is computed by dividing earnings applicable to common stockholders by the weighted-average number of common shares outstanding and assumed to be outstanding. Diluted EPS assumes the dilutive effect of outstanding common stock warrants, shares issued in conjunction with the Company’s ESPP and RSUs, all using the treasury stock method. The following table sets forth the computation of the basic and diluted earnings per share attributable to the Company's common shareholders for the three and nine months ended September 30, 2023 and 2022: Three Months Ended September 30, Nine Months Ended September 30, (in thousands, except per share amounts) 2023 2022 2023 2022 EPS numerator:     Net income $ 7,192  $ 3,641  $ 15,505  $ 2,991  EPS denominator: Weighted average shares outstanding – basic 10,963  10,445  10,696  10,430  Impact of dilutive securities 826  245  976  165  Weighted average shares outstanding – diluted 11,789  10,690  11,672  10,595  EPS: Basic $ 0.66  $ 0.35  $ 1.45  $ 0.29  Diluted $ 0.61  $ 0.34  $ 1.33  $ 0.28  The following table summarizes the securities that were antidilutive or out-of-the-money, and therefore, were not included in the computations of diluted income per common share:   Three Months Ended September 30, Nine Months Ended September 30,   2023 2022 2023 2022 Out-of-the-money warrants (see Note 7) —  1,229,643  —  1,229,643  Service-based RSUs (See Note 14) —  56  49  3,818  Performance and market-based RSUs(1) —  197  153  842  Employee Stock Purchase Plan 33  233  1,114  1,301  Total 33  1,230,129  1,316  1,235,604  (1)    For the three and nine months ended September 30, 2022, certain MRSU awards (each defined in Note 14) were not included in the computation of diluted income per common share because the performance and market conditions were not satisfied during the periods and would not be satisfied if the reporting date was at the end of the contingency period.

v3.23.3

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is taxed as a C corporation. For interim periods, the provision for income taxes (including federal, state, local and foreign taxes) is calculated based on the estimated annual effective tax rate, adjusted for certain discrete items for the full fiscal year. Cumulative adjustments to the Company's estimate are recorded in the interim period in which a change in the estimated annual effective rate is determined. Each quarter the Company updates its estimate of the annual effective tax rate, and if its estimated tax rate changes, the Company makes a cumulative adjustment. The following table presents our income tax provision and our income tax rate for the three and nine months ended September 30, 2023 and 2022. Three Months Ended September 30, Nine Months Ended September 30, (in thousands, except percentages) 2023 2022 2023 2022 Income tax provision $ 2,760  $ 1,654  $ 5,407  $ 1,275  Income tax rate 27.7  % 31.2  % 25.9  % 29.9  % The U.S. federal statutory tax rate was 21% for each of the three and nine months ended September 30, 2023 and 2022. The difference between the U.S. federal statutory tax rate and the Company’s effective tax rate period over period was primarily due to state income taxes, tax credits, other permanent adjustments and discrete tax items. No valuation allowance was required as of September 30, 2023 or December 31, 2022.

v3.23.3

Operating Segments	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Operating Segments	Operating Segments As discussed in Note 1, the Company operates in two segments, (i) GCR, in which the Company generally manages new construction or renovation projects that involve primarily HVAC, plumbing, or electrical services awarded to the Company by general contractors or construction managers, and (ii) ODR, in which the Company provides maintenance or service primarily on HVAC, plumbing or electrical systems, building controls and specialty contracting projects direct to, or assigned by, building owners or property managers. These segments are reflective of how the Company’s Chief Operating Decision Maker (“CODM”) reviews operating results for the purposes of allocating resources and assessing performance. The Company's CODM is comprised of its President and Chief Executive Officer and Executive Vice President and Chief Financial Officer. In accordance with ASC Topic 280 – Segment Reporting, the Company has elected to aggregate all of the GCR work performed at branches into one GCR reportable segment and all of the ODR work performed at branches into one ODR reportable segment. All transactions between segments are eliminated in consolidation. On January 17, 2023, the Company announced its planned transition succession, pursuant to which Charles A. Bacon III stepped down as President and Chief Executive Officer on March 28, 2023, and Michael M. McCann, the Company’s former Executive Vice President and Chief Operating Officer, was appointed President and Chief Executive Officer. Following the transition, the Company revised its segment presentation to align with how Mr. McCann assesses performance and makes resource allocation decisions for its operating segments, which is based on segment revenue and segment gross profit. Selling, general and administrative ("SG&A") expenses are no longer reported on a segment basis as the Company's current CODM does not review discrete segment financial information for SG&A in order to assess performance. Interest expense is not allocated to segments because of the corporate management of debt service. The Company restated segment information for the historical periods presented herein to conform to the current presentation. This change in segment presentation does not affect the Company’s unaudited condensed consolidated statements of operations, balance sheets or statements of cash flows. All of the Company’s identifiable assets are located in the United States, which is where the Company is domiciled. Condensed consolidated segment information for the three and nine months ended September 30, 2023 and 2022 were as follows:   Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2023 2022 2023 2022 Statement of Operations Data:     Revenue:     GCR $ 61,936  $ 62,653  $ 190,329  $ 200,921  ODR 65,832  59,704  183,330  152,378  Total revenue 127,768  122,357  373,659  353,299  Gross profit: GCR 11,970  9,648  33,560  26,700  ODR 19,274  15,206  52,424  37,814  Total gross profit 31,244  24,854  85,984  64,514  Selling, general and administrative(1) 20,967  18,688  62,433  56,113  Change in fair value of contingent consideration 161  386  464  1,151  Amortization of intangibles 288  386  1,054  1,184  Operating income $ 9,828  $ 5,394  $ 22,033  $ 6,066  Less unallocated amounts: Interest expense (437) (547) (1,615) (1,511) Interest income 377  —  624  —  Gain on disposition of property and equipment 68  150  28  262  Loss on early termination of operating lease —  —  —  (849) Loss on early debt extinguishment —  —  (311) —  Gain on change in fair value of interest rate swap 116  298  153  298  Total unallocated amounts 124  (99) (1,121) (1,800) Income before income taxes $ 9,952  $ 5,295  $ 20,912  $ 4,266  (1)    Included within selling, general and administrative expenses was $1.1 million and $0.8 million of stock based compensation expense for the three months ended September 30, 2023 and 2022, respectively. For the nine months ended September 30, 2023 and 2022, selling, general and administrative expenses included $3.4 million and $2.0 million of stock based compensation expenses, respectively. The Company does not identify capital expenditures and total assets by segment in its internal financial reports due in part to the shared use of a centralized fleet of vehicles and specialized equipment. Interest expense is also not allocated to segments because of the Company’s corporate management of debt service, including interest.

v3.23.3

Leases	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Leases	Leases The Company leases real estate, trucks and other equipment. The determination of whether an arrangement is, or contains, a lease is performed at the inception of the arrangement. Classification and initial measurement of the right-of-use asset and lease liability are determined at the lease commencement date. The Company elected the short-term lease measurement and recognition exemption; therefore, leases with an initial term of 12 months or less are not recorded on the condensed consolidated balance sheets. Instead, the short-term leases are recognized in expense on a straight-line basis over the lease term. The Company's arrangements include certain non-lease components such as common area and other maintenance for leased real estate, as well as mileage, fuel and maintenance costs related to leased vehicles. For all leased asset classes, the Company has elected to not separate non-lease components from lease components and will account for each separate lease component and non-lease component associated with the lease as a single lease component. The Company does not guarantee any residual value in its lease agreements, and there are no material restrictions or covenants imposed by lease arrangements. Real estate leases typically include one or more options to extend the lease. The Company regularly evaluates the renewal options, and when they are reasonably certain of exercise, the Company includes the renewal period in its lease term. For the Company's leased vehicles, the Company uses the interest rate implicit in its leases with the lessor to discount lease payments at the lease commencement date. When the implicit rate is not readily available, as is the case with the Company's real estate leases, the Company uses quoted borrowing rates on its secured debt. Related Party Lease Agreements. In conjunction with the closing of the Jake Marshall Transaction, the Company entered into an operating lease for certain land and facilities owned by a former member of JMLLC who became a full-time employee of the Company. The lease term is 10 years and includes an option to extend the lease for two successive periods of two years each through November 2035. Base rent for the term of the lease is $37,500 per month for the first five years with payment commencing on January 1, 2022. The fixed rent payment is escalated to $45,000 per month for years 6 through 10 of the lease term. Fixed rent payments for the extension term shall be increased from $45,000 by the percentage increase, if any, in the consumer price index from the lease commencement date. In addition, under the agreement, the Company is required to pay its share of estimated property taxes and operating expenses, both of which are variable lease expenses. In conjunction with the closing of the ACME Transaction, the Company entered into an operating lease for certain land and facilities owned by a former member of ACME who became a full-time employee of the Company. The lease term of the lease runs through December 31, 2024 and includes an option to extend the lease for one successive period of one year through December 2025. Base rent for the term of the lease is $17,000 per month for the first six months with payment commencing on July 1, 2023. The fixed rent payment is escalated to $18,000 per month for the twelve month period ending December 31, 2024. Fixed rent payments for the extension term shall be increased to $19,000. In addition, under the agreement, the Company is required to pay its share of estimated property taxes and operating expenses, both of which are variable lease expenses. Southern California Sublease. In June, 2021, the Company entered into a sublease agreement with a third party for the entire ground floor of its leased space in Southern California, consisting of 71,787 square feet. Under the terms of the sublease agreement, the sublessee is obligated to pay the Company base rent of approximately $0.6 million per year, which is subject to a 3.0% annual rent increase, plus certain operating expenses and other costs. The initial lease term commenced in September 2021 and continues through April 30, 2027. As of September 30, 2023, the Company remains obligated under the original lease for such office space and, in the event the sublessee of such office space fails to satisfy its obligations under the sublease, the Company would be required to satisfy its obligations directly to the landlord under such original lease. In addition, during the first quarter of 2022, the Company entered into an amendment to the aforementioned sublease agreement, which, among other things, expanded the sublease premises to include the entire second floor of its leased space in Southern California, consisting of 16,720 square feet. Under the terms of the amended sublease agreement, the sublessee is obligated to pay the Company base rent of approximately $0.8 million per year, which is subject to a 3.0% annual rent increase, plus certain operating expenses and other costs. The amended sublease term commenced in March 2022 and continues through April 30, 2027. For the three and nine months ended September 30, 2023, the Company recorded approximately $0.3 million and $0.5 million, respectively, of income in selling, general and administrative expenses related to this sublease agreement. For the three and nine months ended September 30, 2022, the Company recorded approximately $0.2 million and $0.4 million, respectively, of income in selling, general and administrative expenses related to this sublease agreement. Pittsburgh Lease Termination. In March, 2022, the Company entered into a lease termination agreement (the “Lease Termination Agreement”) to terminate, effective March 31, 2022, the lease associated with the Company’s office space located in Pittsburgh, Pennsylvania, which previously served as its corporate headquarters. Absent the Lease Termination Agreement, the lease would have expired in accordance with its terms in July 2025. Pursuant to the Lease Termination Agreement, in exchange for allowing the Company to terminate the lease early, the Company agreed to pay a termination fee in the aggregate of approximately $0.7 million in 16 equal monthly installments commencing on April 1, 2022. The Company recognized the full termination fee expense during the first quarter of 2022. In connection with the lease termination, the Company recognized a gain of $0.1 million associated with the derecognition of the operating lease right-of-use asset and corresponding operating lease liabilities associated with the operating lease and recorded a $0.1 million loss on the disposal of leasehold improvements and moving expenses. The following table summarizes the lease amounts included in the Company's condensed consolidated balance sheets: (in thousands) Classification on the Condensed Consolidated Balance Sheets September 30, 2023 December 31, 2022 Assets Operating Operating lease right-of-use assets(1) $ 15,845  $ 18,288  Finance Property and equipment, net(2)(3) 9,217  7,402  Total lease assets $ 25,062  $ 25,690  Liabilities Current    Operating Current operating lease liabilities $ 3,562  $ 3,562     Finance Current portion of long-term debt 2,472  2,135  Noncurrent    Operating Long-term operating lease liabilities 13,240  15,643     Finance Long-term debt(4) 9,828  8,170  Total lease liabilities $ 29,102  $ 29,510  (1)     Operating lease assets are recorded net of accumulated amortization of $13.0 million at September 30, 2023 and $12.2 million at December 31, 2022. (2)    Finance lease vehicle assets are recorded net of accumulated amortization of $4.9 million at September 30, 2023 and $6.0 million at December 31, 2022. (3)    Includes approximately $2.5 million and $2.6 million of net property assets associated with the Company's Pontiac Facility as of September 30, 2023 and December 31, 2022, respectively. (4)    Includes approximately $5.4 million associated with the Company's sale and leaseback financing transaction. See Note 6 for further detail. The following table summarizes the lease costs included in the Company's condensed consolidated statements of operations for the three and nine months ended September 30, 2023 and 2022: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) Classification on the Condensed Consolidated Statement of Operations 2023 2022 2023 2022 Operating lease cost Cost of revenue(1) $ 543  $ 654  $ 1,626  $ 2,005  Operating lease cost Selling, general and administrative(1) 635  622  1,892  1,957  Finance lease cost    Amortization Cost of revenue(2) 714  684  2,012  2,020     Interest Interest expense, net(2) 113  68  265  200  Total lease cost $ 2,005  $ 2,028  $ 5,795  $ 6,182  (1)    Operating lease costs recorded in cost of revenue included $0.1 million and $0.2 million of variable lease costs for the three months ended September 30, 2023 and 2022, respectively, and $0.3 million and $0.4 million for the nine months ended September 30, 2023 and 2022, respectively. In addition, $0.2 million of variable lease costs are included in selling, general and administrative for each of the three months ended September 30, 2023 and 2022, and $0.4 million for each of the nine months ended September 30, 2023 and 2022. These variable costs consist of the Company's proportionate share of operating expenses, real estate taxes and utilities. (2)     Finance lease costs recorded in cost of revenue include variable lease costs of $0.9 million and $1.0 million for the three months ended September 30, 2023 and 2022, respectively, and $2.7 million and $2.8 million for the nine months ended September 30, 2023 and 2022, respectively. These variable lease costs consist of fuel, maintenance, and sales tax charges. The future undiscounted minimum finance lease payments, as reconciled to the discounted minimum lease obligation indicated on the Company’s condensed consolidated balance sheets within current and long-term debt, less interest, and under current and long-term operating leases, less imputed interest, as of September 30, 2023 were as follows (in thousands): Finance Lease Obligations Operating Lease Obligations Year ending: Vehicles Pontiac Facility Total Finance Non-Related Party Related Party(1) Total Operating Sublease Receipts(2) Remainder of 2023 $ 813  $ 128  $ 941  $ 1,347  $ 218  $ 1,565  $ 224  2024 2,624  515  3,139  3,322  666  3,988  912  2025 2,083  528  2,611  2,787  450  3,237  939  2026 1,567  542  2,109  2,670  450  3,120  967  2027 636  555  1,191  1,693  540  2,233  326  Thereafter —  14,302  14,302  1,536  4,275  5,811  —  Total minimum lease payments 7,723  16,570  24,293  13,355  6,599  19,954  $ 3,369  Financing Component (3) (774) (11,219) (11,993) (1,676) (1,476) (3,152) Net present value of minimum lease payments 6,949  5,351  12,300  11,679  5,123  16,802  Less: current portion of finance and operating lease obligations (2,472) —  (2,472) (3,111) (451) (3,562) Long-term finance and operating lease obligations $ 4,477  $ 5,351  $ 9,828  $ 8,568  $ 4,672  $ 13,240  (1)    Associated with the aforementioned related party leases entered into with former members of JMLLC and ACME. (2)    Associated with the aforementioned third party sublease. (3)     The financing component for finance lease obligations represents the interest component of finance leases that will be recognized as interest expense in future periods. The financing component for operating lease obligations represents the effect of discounting the lease payments to their present value. The following is a summary of the lease terms and discount rates as of: September 30, 2023 December 31, 2022 Weighted average lease term (in years):    Operating 6.50 6.98    Finance (1) 3.12 2.73 Weighted average discount rate:    Operating 4.91  % 4.76  %    Finance (1) 6.66  % 5.06  % (1)     Excludes the weighted average lease term and weighted average discount rate associated with the aforementioned sale-leaseback financing transaction, which has a Primary Term of 25 years and utilized an implicit rate of 11.11%. See Note 6 for further detail. The following is a summary of other information and supplemental cash flow information related to finance and operating leases: Nine months ended September 30, (in thousands) 2023 2022 Cash paid for amounts included in the measurement of lease liabilities:    Operating cash flows from operating leases $ 3,478  $ 3,890     Operating cash flows from finance leases 227  200     Financing cash flows from finance leases 2,032  2,051  Right-of-use assets exchanged for lease liabilities:    Operating leases 1,043  —     Finance leases 4,062  2,171  Right-of-use assets disposed or adjusted modifying operating leases liabilities (643) 2,396  Right-of-use assets disposed or adjusted modifying finance leases liabilities $ (77) (77)
Leases	Leases The Company leases real estate, trucks and other equipment. The determination of whether an arrangement is, or contains, a lease is performed at the inception of the arrangement. Classification and initial measurement of the right-of-use asset and lease liability are determined at the lease commencement date. The Company elected the short-term lease measurement and recognition exemption; therefore, leases with an initial term of 12 months or less are not recorded on the condensed consolidated balance sheets. Instead, the short-term leases are recognized in expense on a straight-line basis over the lease term. The Company's arrangements include certain non-lease components such as common area and other maintenance for leased real estate, as well as mileage, fuel and maintenance costs related to leased vehicles. For all leased asset classes, the Company has elected to not separate non-lease components from lease components and will account for each separate lease component and non-lease component associated with the lease as a single lease component. The Company does not guarantee any residual value in its lease agreements, and there are no material restrictions or covenants imposed by lease arrangements. Real estate leases typically include one or more options to extend the lease. The Company regularly evaluates the renewal options, and when they are reasonably certain of exercise, the Company includes the renewal period in its lease term. For the Company's leased vehicles, the Company uses the interest rate implicit in its leases with the lessor to discount lease payments at the lease commencement date. When the implicit rate is not readily available, as is the case with the Company's real estate leases, the Company uses quoted borrowing rates on its secured debt. Related Party Lease Agreements. In conjunction with the closing of the Jake Marshall Transaction, the Company entered into an operating lease for certain land and facilities owned by a former member of JMLLC who became a full-time employee of the Company. The lease term is 10 years and includes an option to extend the lease for two successive periods of two years each through November 2035. Base rent for the term of the lease is $37,500 per month for the first five years with payment commencing on January 1, 2022. The fixed rent payment is escalated to $45,000 per month for years 6 through 10 of the lease term. Fixed rent payments for the extension term shall be increased from $45,000 by the percentage increase, if any, in the consumer price index from the lease commencement date. In addition, under the agreement, the Company is required to pay its share of estimated property taxes and operating expenses, both of which are variable lease expenses. In conjunction with the closing of the ACME Transaction, the Company entered into an operating lease for certain land and facilities owned by a former member of ACME who became a full-time employee of the Company. The lease term of the lease runs through December 31, 2024 and includes an option to extend the lease for one successive period of one year through December 2025. Base rent for the term of the lease is $17,000 per month for the first six months with payment commencing on July 1, 2023. The fixed rent payment is escalated to $18,000 per month for the twelve month period ending December 31, 2024. Fixed rent payments for the extension term shall be increased to $19,000. In addition, under the agreement, the Company is required to pay its share of estimated property taxes and operating expenses, both of which are variable lease expenses. Southern California Sublease. In June, 2021, the Company entered into a sublease agreement with a third party for the entire ground floor of its leased space in Southern California, consisting of 71,787 square feet. Under the terms of the sublease agreement, the sublessee is obligated to pay the Company base rent of approximately $0.6 million per year, which is subject to a 3.0% annual rent increase, plus certain operating expenses and other costs. The initial lease term commenced in September 2021 and continues through April 30, 2027. As of September 30, 2023, the Company remains obligated under the original lease for such office space and, in the event the sublessee of such office space fails to satisfy its obligations under the sublease, the Company would be required to satisfy its obligations directly to the landlord under such original lease. In addition, during the first quarter of 2022, the Company entered into an amendment to the aforementioned sublease agreement, which, among other things, expanded the sublease premises to include the entire second floor of its leased space in Southern California, consisting of 16,720 square feet. Under the terms of the amended sublease agreement, the sublessee is obligated to pay the Company base rent of approximately $0.8 million per year, which is subject to a 3.0% annual rent increase, plus certain operating expenses and other costs. The amended sublease term commenced in March 2022 and continues through April 30, 2027. For the three and nine months ended September 30, 2023, the Company recorded approximately $0.3 million and $0.5 million, respectively, of income in selling, general and administrative expenses related to this sublease agreement. For the three and nine months ended September 30, 2022, the Company recorded approximately $0.2 million and $0.4 million, respectively, of income in selling, general and administrative expenses related to this sublease agreement. Pittsburgh Lease Termination. In March, 2022, the Company entered into a lease termination agreement (the “Lease Termination Agreement”) to terminate, effective March 31, 2022, the lease associated with the Company’s office space located in Pittsburgh, Pennsylvania, which previously served as its corporate headquarters. Absent the Lease Termination Agreement, the lease would have expired in accordance with its terms in July 2025. Pursuant to the Lease Termination Agreement, in exchange for allowing the Company to terminate the lease early, the Company agreed to pay a termination fee in the aggregate of approximately $0.7 million in 16 equal monthly installments commencing on April 1, 2022. The Company recognized the full termination fee expense during the first quarter of 2022. In connection with the lease termination, the Company recognized a gain of $0.1 million associated with the derecognition of the operating lease right-of-use asset and corresponding operating lease liabilities associated with the operating lease and recorded a $0.1 million loss on the disposal of leasehold improvements and moving expenses. The following table summarizes the lease amounts included in the Company's condensed consolidated balance sheets: (in thousands) Classification on the Condensed Consolidated Balance Sheets September 30, 2023 December 31, 2022 Assets Operating Operating lease right-of-use assets(1) $ 15,845  $ 18,288  Finance Property and equipment, net(2)(3) 9,217  7,402  Total lease assets $ 25,062  $ 25,690  Liabilities Current    Operating Current operating lease liabilities $ 3,562  $ 3,562     Finance Current portion of long-term debt 2,472  2,135  Noncurrent    Operating Long-term operating lease liabilities 13,240  15,643     Finance Long-term debt(4) 9,828  8,170  Total lease liabilities $ 29,102  $ 29,510  (1)     Operating lease assets are recorded net of accumulated amortization of $13.0 million at September 30, 2023 and $12.2 million at December 31, 2022. (2)    Finance lease vehicle assets are recorded net of accumulated amortization of $4.9 million at September 30, 2023 and $6.0 million at December 31, 2022. (3)    Includes approximately $2.5 million and $2.6 million of net property assets associated with the Company's Pontiac Facility as of September 30, 2023 and December 31, 2022, respectively. (4)    Includes approximately $5.4 million associated with the Company's sale and leaseback financing transaction. See Note 6 for further detail. The following table summarizes the lease costs included in the Company's condensed consolidated statements of operations for the three and nine months ended September 30, 2023 and 2022: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) Classification on the Condensed Consolidated Statement of Operations 2023 2022 2023 2022 Operating lease cost Cost of revenue(1) $ 543  $ 654  $ 1,626  $ 2,005  Operating lease cost Selling, general and administrative(1) 635  622  1,892  1,957  Finance lease cost    Amortization Cost of revenue(2) 714  684  2,012  2,020     Interest Interest expense, net(2) 113  68  265  200  Total lease cost $ 2,005  $ 2,028  $ 5,795  $ 6,182  (1)    Operating lease costs recorded in cost of revenue included $0.1 million and $0.2 million of variable lease costs for the three months ended September 30, 2023 and 2022, respectively, and $0.3 million and $0.4 million for the nine months ended September 30, 2023 and 2022, respectively. In addition, $0.2 million of variable lease costs are included in selling, general and administrative for each of the three months ended September 30, 2023 and 2022, and $0.4 million for each of the nine months ended September 30, 2023 and 2022. These variable costs consist of the Company's proportionate share of operating expenses, real estate taxes and utilities. (2)     Finance lease costs recorded in cost of revenue include variable lease costs of $0.9 million and $1.0 million for the three months ended September 30, 2023 and 2022, respectively, and $2.7 million and $2.8 million for the nine months ended September 30, 2023 and 2022, respectively. These variable lease costs consist of fuel, maintenance, and sales tax charges. The future undiscounted minimum finance lease payments, as reconciled to the discounted minimum lease obligation indicated on the Company’s condensed consolidated balance sheets within current and long-term debt, less interest, and under current and long-term operating leases, less imputed interest, as of September 30, 2023 were as follows (in thousands): Finance Lease Obligations Operating Lease Obligations Year ending: Vehicles Pontiac Facility Total Finance Non-Related Party Related Party(1) Total Operating Sublease Receipts(2) Remainder of 2023 $ 813  $ 128  $ 941  $ 1,347  $ 218  $ 1,565  $ 224  2024 2,624  515  3,139  3,322  666  3,988  912  2025 2,083  528  2,611  2,787  450  3,237  939  2026 1,567  542  2,109  2,670  450  3,120  967  2027 636  555  1,191  1,693  540  2,233  326  Thereafter —  14,302  14,302  1,536  4,275  5,811  —  Total minimum lease payments 7,723  16,570  24,293  13,355  6,599  19,954  $ 3,369  Financing Component (3) (774) (11,219) (11,993) (1,676) (1,476) (3,152) Net present value of minimum lease payments 6,949  5,351  12,300  11,679  5,123  16,802  Less: current portion of finance and operating lease obligations (2,472) —  (2,472) (3,111) (451) (3,562) Long-term finance and operating lease obligations $ 4,477  $ 5,351  $ 9,828  $ 8,568  $ 4,672  $ 13,240  (1)    Associated with the aforementioned related party leases entered into with former members of JMLLC and ACME. (2)    Associated with the aforementioned third party sublease. (3)     The financing component for finance lease obligations represents the interest component of finance leases that will be recognized as interest expense in future periods. The financing component for operating lease obligations represents the effect of discounting the lease payments to their present value. The following is a summary of the lease terms and discount rates as of: September 30, 2023 December 31, 2022 Weighted average lease term (in years):    Operating 6.50 6.98    Finance (1) 3.12 2.73 Weighted average discount rate:    Operating 4.91  % 4.76  %    Finance (1) 6.66  % 5.06  % (1)     Excludes the weighted average lease term and weighted average discount rate associated with the aforementioned sale-leaseback financing transaction, which has a Primary Term of 25 years and utilized an implicit rate of 11.11%. See Note 6 for further detail. The following is a summary of other information and supplemental cash flow information related to finance and operating leases: Nine months ended September 30, (in thousands) 2023 2022 Cash paid for amounts included in the measurement of lease liabilities:    Operating cash flows from operating leases $ 3,478  $ 3,890     Operating cash flows from finance leases 227  200     Financing cash flows from finance leases 2,032  2,051  Right-of-use assets exchanged for lease liabilities:    Operating leases 1,043  —     Finance leases 4,062  2,171  Right-of-use assets disposed or adjusted modifying operating leases liabilities (643) 2,396  Right-of-use assets disposed or adjusted modifying finance leases liabilities $ (77) (77)

v3.23.3

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal. The Company is continually engaged in administrative proceedings, arbitrations, and litigation with owners, general contractors, suppliers, employees, former employees and other unrelated parties, all arising in the ordinary courses of business. The ultimate resolution of these contingencies could, individually or in the aggregate, be material to the condensed consolidated financial statements. In the opinion of the Company’s management, the current belief is that the results of these actions will not have a material adverse effect on the financial position, results of operations, or cash flows of the Company. On January 23, 2020, plaintiff, Bernards Bros. Inc. (“Bernards”), filed a complaint against the Company in Superior Court of the State of California for the County of Los Angeles. The complaint alleges that the Company's Southern California business unit refused to honor a proposal made to Bernards to act as a subcontractor on a construction project, and that, as a result of the wrongful failure to honor the proposal, Bernards suffered damages in excess of $3.0 million plus interest, including alleged increased costs for hiring a different subcontractor to perform the work. The Company has vigorously defended the suit. Per the agreement of the Company and Bernards, in January 2022, the Court appointed a private referee to manage the case and adjudicate the dispute. A trial took place before the referee in January 2023, and on April 30, 2023, the referee issued an Amended Statement of Decision awarding Bernards approximately $2.2 million. As of December 31, 2022, the Company had determined that a loss was probable, and, as such, recorded an estimated loss contingency in the amount of $2.2 million, which is included in accrued expenses and other current liabilities reported within the Company’s consolidated balance sheets. In addition, the estimated loss contingency was recorded within selling, general and administrative expenses on the Company’s consolidated statements of operations. The Company is currently evaluating its options to appeal the referee's decisions. Surety. The terms of its construction contracts frequently require that the Company obtain from surety companies, and provide to its customers, payment and performance bonds (“Surety Bonds”) as a condition to the award of such contracts. The Surety Bonds secure the Company's payment and performance obligations under such contracts, and the Company has agreed to indemnify the surety companies for amounts, if any, paid by them in respect of Surety Bonds issued on its behalf. In addition, at the request of labor unions representing certain of the Company's employees, Surety Bonds are sometimes provided to secure obligations for wages and benefits payable to or for such employees. Public sector contracts require Surety Bonds more frequently than private sector contracts, and accordingly, the Company's bonding requirements typically increase as the amount of public sector work increases. As of September 30, 2023, the Company had approximately $99.7 million in surety bonds outstanding. The Surety Bonds are issued by surety companies in return for premiums, which vary depending on the size and type of bond. Collective Bargaining Agreements. Many of the Company’s craft labor employees are covered by collective bargaining agreements. The agreements require the Company to pay specified wages, provide certain benefits and contribute certain amounts to multi-employer pension plans. If the Company withdraws from any of the multi-employer pension plans or if the plans were to otherwise become underfunded, the Company could incur additional liabilities related to these plans. Although the Company has been informed that some of the multi-employer pension plans to which it contributes have been classified as “critical” status, the Company is not currently aware of any significant liabilities related to this issue. Self-insurance. The Company is substantially self-insured for workers’ compensation and general liability claims, in the view of the relatively high per-incident deductibles the Company absorbs under its insurance arrangements for these risks. The Company purchases workers’ compensation and general liability insurance under policies with per-incident deductibles of $250,000 per occurrence and a $4.4 million maximum aggregate deductible loss limit per year. Losses incurred over primary policy limits are covered by umbrella and excess policies up to specified limits with multiple excess insurers. The Company accrues for the unfunded portion of costs for both reported claims and claims incurred but not reported. The liability for unfunded reported claims and future claims is reflected on the consolidated balance sheets as current and non-current liabilities. The liability is determined by establishing a reserve for each reported claim on a case-by-case basis based on the nature of the claim and historical loss experience for similar claims plus an allowance for the cost of incurred but not reported claims. The current portion of the liability is included in accrued expenses and other current liabilities on the consolidated balance sheets. The non-current portion of the liability is included in other long-term liabilities on the consolidated balance sheets. The Company is self-insured related to medical and dental claims under policies with annual per-claimant and annual aggregate stop-loss limits. The Company accrues for the unfunded portion of costs for both reported claims and claims incurred but not reported. The liability for unfunded reported claims and future claims is reflected on the consolidated balance sheets as a current liability in accrued expenses and other current liabilities. The components of the self-insurance liability as of September 30, 2023 and December 31, 2022 are as follows: (in thousands) September 30, 2023 December 31, 2022 Current liability — workers’ compensation and general liability $ 99  $ 158  Current liability — medical and dental 422  557  Non-current liability 746  343  Total liability $ 1,267  $ 1,058  Restricted cash $ 65  $ 113  The restricted cash balance represents an imprest cash balance set aside for the funding of workers' compensation and general liability insurance claims. This amount is replenished either when depleted or at the beginning of each month.

v3.23.3

Management Incentive Plans	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Management Incentive Plans	Management Incentive Plans The Company initially adopted the Omnibus Incentive Plan on July 20, 2016 for the purpose of: (a) encouraging the profitability and growth of the Company through short-term and long-term incentives that are consistent with the Company’s objectives; (b) giving participants an incentive for excellence in individual performance; (c) promoting teamwork among participants; and (d) giving the Company a significant advantage in attracting and retaining key employees, directors and consultants. To accomplish such purposes, the Omnibus Incentive Plan, and such subsequent amendments to the Omnibus Incentive Plan, provides that the Company may grant options, stock appreciation rights, restricted shares, RSUs, performance-based awards (including performance-based restricted shares and restricted stock units), other share based awards, other cash-based awards or any combination of the foregoing. Following the approval of the 2023 Amended and Restated Omnibus Incentive Plan, the Company has reserved 3,050,000 shares of its common stock for issuance. The number of shares issued or reserved pursuant to the Omnibus Incentive Plan will be adjusted by the plan administrator, as they deem appropriate and equitable, as a result of stock splits, stock dividends, and similar changes in the Company’s common stock. In connection with the grant of an award, the plan administrator may provide for the treatment of such award in the event of a change in control. All awards are made in the form of shares only. Service-Based Awards The Company grants service-based stock awards in the form of RSUs. Service-based RSUs granted to executives, employees, and non-employee directors vest ratably, on an annual basis, over three years and in the case of certain awards to non-employee directors, one year. The grant date fair value of the service-based awards was equal to the closing market price of the Company’s common stock on the date of grant. For both the three months ended September 30, 2023 and 2022, the Company recognized $0.5 million of stock-based compensation expense related to outstanding service-based RSUs. For both the nine months ended September 30, 2023 and 2022, the Company recognized $1.2 million of stock-based compensation expense related to outstanding service-based RSUs during both periods. The following table summarizes the Company's service-based RSU activity for the nine months ended September 30, 2023:   Awards Weighted-Average Grant Date Fair Value Unvested at December 31, 2022 280,275  $ 9.06  Granted 164,413  11.94  Vested (163,354) 8.58  Forfeited (42,131) 10.63  Unvested at September 30, 2023 239,203  $ 11.09  Performance-Based Awards The Company grants performance-based restricted stock units (“PRSUs”) under which shares of the Company’s common stock may be earned based on the Company’s performance compared to defined metrics. The number of shares earned under a performance award may vary from zero to 150% of the target shares awarded, based upon the Company’s performance compared to the metrics. The metrics used for the grant are determined by the Company’s Compensation Committee of the Board of Directors and are based on internal measures such as the achievement of certain predetermined adjusted EBITDA, EPS growth and EBITDA margin performance goals over a three year period. The Company recognizes stock-based compensation expense for these awards over the vesting period based on the projected probability of achievement of the performance conditions as of the end of each reporting period during the performance period and may periodically adjust the recognition of such expense, as necessary, in response to any changes in the Company’s forecasts with respect to the performance conditions. For the three months ended September 30, 2023 and 2022, the Company recognized $0.7 million and $0.3 million, respectively, of stock-based compensation expense related to outstanding PRSUs. For the nine months ended September 30, 2023 and 2022, the Company recognized $2.2 million and $0.7 million, respectively, of stock-based compensation expense related to outstanding PRSUs. The following table summarizes the Company's PRSU activity for the nine months ended September 30, 2023:   Awards Weighted-Average Grant Date Fair Value Unvested at December 31, 2022 497,940  $ 8.32  Granted 289,092  12.77  Performance factor adjustment(1) 32,327  4.29  Vested (121,827) 4.29  Forfeited (116,911) 9.81  Unvested at September 30, 2023 580,621  $ 10.85  (1)     Performance-based awards covering the three year period ended December 31, 2022 were paid out in the first quarter of 2023 based on the approval of the Company's Compensation Committee. The performance factor during the measurement period used to determine compensation payouts was 136.13% of the pre-defined metric target of 100%, which resulted in a positive performance factor adjustment and the issuance of 32,327 of additional awards associated with the original grant. Market-Based Awards The vesting of the Company's market-based RSU (“MRSUs”) was contingent upon the Company’s closing price of a share of the Company's common stock on the Nasdaq Capital market, or such other applicable principal securities exchange or quotation system, achieving at least $18.00 over a period of eighty consecutive trading days during the three-year period commencing on August 1, 2018 and concluding on July 31, 2021. On September 4, 2020, the Compensation Committee of the Board of Directors of the Company approved amendments to modify the MRSUs to extend the measurement period to July 16, 2022. In addition to the market performance-based vesting condition, the vesting of such restricted stock unit was subject to continued employment from August 1, 2017 through the later of July 31, 2019 or the date on which the Compensation Committee certifies the achievement of the performance goal. The Company accounted for this amendment as a Type I modification and recognized approximately $0.2 million of incremental stock-based compensation expense over 1.26 years from the modification date based on an updated Monte Carlo simulation model. These awards expired on July 16, 2022 as the MRSU award market condition was not achieved. Stock-Based Compensation Expense Total recognized stock-based compensation expense amounted to $1.1 million and $0.8 million for the three months ended September 30, 2023 and 2022, respectively. For the nine months ended September 30, 2023 and 2022, the Company recognized stock-based compensation expense of $3.4 million and $2.0 million, respectively. The aggregate fair value as of the vest date of RSUs that vested during the nine months ended September 30, 2023 and 2022 was $3.8 million and $1.1 million, respectively. Total unrecognized stock-based compensation expense related to unvested RSUs which are probable of vesting was $3.9 million at September 30, 2023. These costs are expected to be recognized over a weighted average period of 1.68 years.

v3.23.3

Subsequent Events	9 Months Ended
	Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn November 1, 2023, the Company completed an acquisition of Greensboro, NC-based specialty mechanical contractor, Industrial Air, LLC (“Industrial Air”), for a purchase price at closing of $13.5 million in cash. The transaction also provides for an earnout of up to $6.5 million potentially being paid out over the next two years. Industrial Air serves industrial customers throughout the Southeast United States and along the Eastern seaboard, focusing on delivering engineered air handling systems, including air condition and air filtration, along with controls systems and maintenance work. In addition, Industrial Air manufactures a wide range of components for air conditioning and filtration systems.

v3.23.3

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation References in these financial statements to the Company refer collectively to the accounts of Limbach Holdings, Inc. and its wholly-owned subsidiaries, including LHLLC, Limbach Facility Services LLC (“LFS”), Limbach Company LLC (“LC LLC”), Limbach Company LP, Harper Limbach LLC, Harper Limbach Construction LLC, Limbach Facility & Project Solutions LLC, Jake Marshall, LLC (“JMLLC”), Coating Solutions, LLC (“CSLLC”) and ACME Industrial Piping, LLC (“ACME”) for all periods presented, unless otherwise indicated. All intercompany balances and transactions have been eliminated. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the requirements of Form 10-Q and Rule 8-03 of Regulation S-X for smaller reporting companies. Consequently, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. Readers of this report should refer to the consolidated financial statements and the notes thereto included in the Company's most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 8, 2023.
Use of Estimates	Use of Estimates The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements for assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, the reported amounts of revenue and expenses during the reported period, and the accompanying notes. Management believes that its most significant estimates and assumptions have been based on reasonable and supportable assumptions and the resulting estimates are reasonable for use in the preparation of the condensed consolidated financial statements. The Company’s significant estimates include estimates associated with revenue recognition on construction contracts, costs incurred through each balance sheet date, intangibles, property and equipment, fair value accounting for acquisitions, insurance reserves, fair value of contingent consideration arrangements and contingencies. If the underlying estimates and assumptions upon which the condensed consolidated financial statements are based change in the future, actual amounts may differ from those included in the accompanying condensed consolidated financial statements.
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying interim Condensed Consolidated Balance Sheets, Condensed Consolidated Statements of Operations, Condensed Consolidated Statements of Stockholders’ Equity and Condensed Consolidated Statements of Cash Flows for the periods presented are unaudited. Also, within the notes to the condensed consolidated financial statements, the Company has included unaudited information for these interim periods. These unaudited interim condensed consolidated financial statements have been prepared in accordance with GAAP. In the Company's opinion, the accompanying unaudited condensed consolidated financial statements contain all normal and recurring adjustments necessary for a fair statement of the Company’s financial position as of September 30, 2023, its results of operations and equity for the three and nine months ended September 30, 2023 and 2022 and its cash flows for the nine months ended September 30, 2023 and 2022. The results for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023. The Condensed Consolidated Balance Sheet as of December 31, 2022 was derived from the Company's audited financial statements included in its Annual Report on Form 10-K filed with the SEC on March 8, 2023, but is presented as condensed and does not contain all of the footnote disclosures from the annual financial statements.
Recently Adopted Accounting Standards and Recent Accounting Pronouncements	Recently Adopted Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments, which introduced an expected credit loss methodology for the measurement and recognition of credit losses on most financial instruments, including trade receivables and off-balance sheet credit exposure. Under this guidance, an entity is required to consider a broader range of information to estimate expected credit losses, which may result in earlier recognition of losses. This ASU also requires disclosure of information regarding how a company developed its allowance, including changes in the factors that influenced management’s estimate of expected credit losses and the reasons for those changes. The Company adopted ASU 2016-13 on January 1, 2023 using the modified retrospective method, whereby the guidance was applied prospectively as of the date of adoption and prior periods are not restated. The adoption of this ASU did not have a material impact on the Company's financial position or results of operations. The Company assessed the scope of its financial assets and determined that the guidance associated with ASU 2016-13 is relevant to its trade accounts receivable and contract assets, including retainage. The Company’s trade receivables include amounts from work completed in which it has billed or has an unconditional right to bill its customers. The majority of the Company’s trade receivables are contractually due in less than a year. The Company further assessed the guidance based on its segment portfolio of receivables. While the Company’s construction-type GCR and ODR financial assets are often in the same subset of customers and industries, the Company’s construction-type related project work is typically bonded and the customers to which they perform work are well-known, solvent and have no history of material receivable write-offs. On the contrary, the Company’s service-type work, in particular its ODR core service work, is smaller in nature and is usually more susceptible to customer write-offs. As such, there is greater risk of credit loss on the Company’s ODR-related service-type receivables. The Company’s contract assets include amounts due under retainage provisions and costs and estimated earnings in excess of billings on uncompleted contracts. The Company has policies and procedures in place where it reviews claims and change orders on a quarterly basis to determine legal entitlement and recoverability in accordance with ASC Topic 606. As such, the Company has determined the risk of credit loss on its contracts assets to be remote. The Company develops its allowances for credit losses, which represent an estimate of expected losses over the remaining contractual life of its ODR-related service-type receivables, using an aging method. Under the aging method, the Company assigns its accounts receivable to a level of delinquency and applies a loss rate to each class. Loss rates are determined based on historical loss experiences with customers, the consideration of a customer’s financial condition, current market economic conditions and a forecast of future economic conditions when appropriate. When the Company becomes aware of a customer's inability to meet its financial obligation, a specific reserve is recorded to reduce the receivable to the expected amount to be collected. As part of the Company’s analysis of expected credit losses, it may analyze receivables with customers on an individual basis in situations where such accounts receivables exhibit unique risk characteristics and are not expected to experience similar losses to the rest of their class. Recent Accounting Pronouncements The FASB has issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting in March 2020. This new guidance provides optional expedients for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform, on financial reporting. The risk of termination of the London Interbank Offered Rate (LIBOR), has caused regulators to undertake reference rate reform initiatives to identify alternative reference rates that are more observable or transaction based that are less susceptible to manipulation. ASU 2020-04 was effective between March 12, 2020 and December 31, 2022. However, in December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, extending the sunset date under Topic 848 from December 31, 2022 to December 31, 2024 to align the temporary accounting relief guidance with the expected LIBOR cessation date of June 30, 2023. In addition, in January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848): Scope. The amendments in this update refine the scope for certain optional expedients and exceptions for contract modifications and hedge accounting to apply to derivative contracts and certain hedging relationships affected by the discounting transition. As a result of ASU 2022-06, an entity may now elect to apply the amendments in this update from the beginning of an interim period beginning as of March 12, 2020, through December 31, 2024. The Company has evaluated the impact of adopting the reference rate reform guidance (both ASU 2020-04 and ASU 2021-01) on its consolidated financial statements and has determined that these pronouncements did not have a significant impact. As discussed in Note 6, the A&R Credit Agreement removed LIBOR as a benchmark rate and now utilizes SOFR (as defined in the A&R Credit Agreement) as its replacement. During the second quarter of 2023, the Company entered into the Second A&R Credit Agreement (as defined in Note 6), which also utilizes SOFR as a benchmark rate. In addition, the Company’s interest rate swap utilizes SOFR as its benchmark rate. In August 2020, the FASB issued ASU 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity, which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity and amends the scope guidance for contracts in an entity's own equity. The ASU addresses how convertible instruments are accounted for in the calculation of diluted earnings per share by using the if-converted method. The guidance is effective for all entities for fiscal years beginning after March 31, 2024, albeit early adoption is permitted no earlier than fiscal years beginning after December 15, 2020. Management is currently assessing the impact of this pronouncement on its condensed consolidated financial statements.
Revenue from Contract with Customers	Revenue from Contracts with Customers The Company generates revenue from construction type contracts, primarily consisting of fixed-price contracts, to deliver HVAC, plumbing, and electrical construction services to its customers. The duration of its contracts generally ranges from three months to two years. Revenue from fixed price contracts is recognized on the cost-to-cost method, measured by the relationship of total cost incurred to total estimated contract costs. Revenue from time and materials contracts is recognized as services are performed. The Company believes that its extensive experience in HVAC, plumbing, and electrical projects, and its internal cost review procedures during the bidding process, enable it to reasonably estimate costs and mitigate the risk of cost overruns on fixed price contracts. The Company generally invoices customers on a monthly basis, based on a schedule of values that breaks down the contract amount into discrete billing items. Costs and estimated earnings in excess of billings on uncompleted contracts are recorded as a contract asset until billable under the contract terms. Billings in excess of costs and estimated earnings on uncompleted contracts are recorded as a contract liability until the related revenue is recognizable. The Company classifies contract assets and liabilities that may be settled beyond one year from the balance sheet date as current, consistent with the length of time of the Company’s project operating cycle. Retainage receivable represents amounts invoiced to customers where payments have been partially withheld, typically 10%, pending the completion of certain milestones, satisfaction of other contractual conditions or the completion of the project. Retainage agreements vary from project to project and balances could be outstanding for several months or years depending on a number of circumstances such as contract-specific terms, project performance and other variables that may arise as the Company makes progress towards completion.Contract assets represent the excess of contract costs and profits (or contract revenue) over the amount of contract billings to date and are classified as a current asset. Contract assets result when either: (1) the appropriate contract revenue amount has been recognized over time in accordance with ASC Topic 606, but a portion of the revenue recorded cannot be currently billed due to the billing terms defined in the contract, or (2) costs are incurred related to certain claims and unapproved change orders. Claims occur when there is a dispute regarding both a change in the scope of work and the price associated with that change. Unapproved change orders occur when a change in the scope of work results in additional work being performed before the parties have agreed on the corresponding change in the contract price. The Company routinely estimates recovery related to claims and unapproved change orders as a form of variable consideration at the most likely amount it expects to receive and to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. Claims and unapproved change orders are billable upon the agreement and resolution between the contractual parties and after the execution of contractual amendments. Increases in claims and unapproved change orders typically result from costs being incurred against existing or new positions; decreases normally result from resolutions and subsequent billings. Billings in excess of costs and estimated earnings on uncompleted contracts represent the excess of contract billings to date over the amount of contract costs and profits (or contract revenue) recognized to date. The balance may fluctuate depending on the timing of contract billings and the recognition of contract revenue. Provisions for losses are recognized in the condensed consolidated statements of operations at the uncompleted performance obligation level for the amount of total estimated losses in the period that evidence indicates that the estimated total cost of a performance obligation exceeds its estimated total revenue. Remaining Performance Obligations Remaining performance obligations represent the transaction price of firm orders for which work has not been performed and exclude unexercised contract options. The Company’s remaining performance obligations include projects that have a written award, a letter of intent, a notice to proceed or an agreed upon work order to perform work on mutually accepted terms and conditions. Additionally, the difference between remaining performance obligations and backlog is due to the exclusion of a portion of the Company’s ODR agreements under certain contract types from the Company’s remaining performance obligations as these contracts can be canceled for convenience at any time by the Company or the customer without considerable cost incurred by the customer.
Fair Value Measurements	The Company measures the fair value of financial assets and liabilities in accordance with ASC Topic 820 – Fair Value Measurements and Disclosures, which defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements. ASC Topic 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value and requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows: •Level 1 — inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that are accessible at the measurement date; •Level 2 — inputs other than quoted prices included in Level 1 that are observable for the asset or liability either directly or indirectly such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities; and •Level 3 — unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

v3.23.3

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2023
Business Combination and Asset Acquisition [Abstract]
Schedule of Allocation of Fair Value of Assets and Liabilities from Jake Marshall Transaction	The following table summarizes the preliminary allocation of the fair value of the assets and liabilities of the ACME Transaction as of the Effective Date by the Company. (in thousands) Purchase Price Allocation Consideration: Cash $ 5,181  Earnout provision 1,121  Total Consideration 6,302  Fair value of assets acquired: Cash and cash equivalents 298  Accounts receivable 1,150  Contract assets 414  Property and equipment 488  Operating lease right-of-use assets 301  Intangible assets 2,300  Amount attributable to assets acquired 4,951  Fair value of liabilities assumed: Accounts payable, including retainage 170  Current operating lease liabilities 195  Accrued expenses and other current liabilities 138  Contract liabilities 373  Long-term operating lease liabilities 106  Amount attributable to liabilities assumed 982  Goodwill $ 2,333
Schedule of Finite-Lived Intangible Assets	Intangible assets, net as of September 30, 2023 are detailed below. (in thousands) Gross Carrying Amount Accumulated Amortization Net Intangible Assets Weighted Average Useful Life (Years) Trade name and trademarks $ 400 $ (18) $ 382 5.5 Customer relationships 1,900 (46) 1,854 10.3 Total $ 2,300 $ (64) $ 2,236 6.3

v3.23.3

Revenue from Contracts with Customers (Tables)	9 Months Ended
	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Schedule of Components of Contract Asset and Liability Balances	Contract assets include amounts due under retainage provisions and costs and estimated earnings in excess of billings on uncompleted contracts. The components of the contract asset balances as of the respective dates were as follows: (in thousands) September 30, 2023 December 31, 2022 Change Contract assets Costs and estimated earnings in excess of billings on uncompleted contracts $ 26,007  $ 33,573  $ (7,566) Retainage receivable 21,846  27,880  (6,034)       Total contract assets $ 47,853  $ 61,453  $ (13,600) Contract liabilities include billings in excess of contract costs and provisions for losses. The components of the contract liability balances as of the respective dates were as follows: (in thousands) September 30, 2023 December 31, 2022 Change Contract liabilities Billings in excess of costs and estimated earnings on uncompleted contracts $ 46,545  $ 43,806  $ 2,739  Provisions for losses 147  201  (54)       Total contract liabilities $ 46,692  $ 44,007  $ 2,685
Schedule of Contracts In Progress	The net (overbilling) underbilling position for contracts in process consisted of the following: (in thousands) September 30, 2023 December 31, 2022 Revenue earned on uncompleted contracts $ 625,765  $ 678,014  Less: Billings to date (646,303) (688,247)    Net (overbilling) underbilling $ (20,538) $ (10,233) (in thousands) September 30, 2023 December 31, 2022 Costs in excess of billings and estimated earnings on uncompleted contracts $ 26,007  $ 33,573  Billings in excess of costs and estimated earnings on uncompleted contracts (46,545) (43,806)    Net (overbilling) underbilling $ (20,538) $ (10,233)

v3.23.3

Goodwill and Intangibles (Tables)	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table summarizes the carrying amount and changes in goodwill associated with the Company's segments for the nine months ended September 30, 2022 and for the year ended December 31, 2022. (in thousands) GCR ODR Total Goodwill as of January 1, 2022 $ —  $ 11,370  $ 11,370  Goodwill as of December 31, 2022 —  11,370  11,370  Goodwill associated with the ACME Transaction —  2,333  2,333  Goodwill as of September 30, 2023 $ —  $ 13,703  $ 13,703
Schedule of Intangible Assets	Intangible assets are comprised of the following:      (in thousands) Gross carrying amount Accumulated amortization Net intangible assets, excluding goodwill September 30, 2023 Amortized intangible assets: Customer relationships – GCR – Jake Marshall $ 570  $ (148) $ 422  Customer relationships – ODR – Jake Marshall 3,050  (737) 2,313  Customer relationships – ODR – ACME 1,900  (46) 1,854  Customer relationships – ODR – Limbach 4,710  (3,944) 766  Favorable leasehold interests – Limbach 190  (109) 81  Backlog – GCR – Jake Marshall 260  (260) —  Backlog – ODR – Jake Marshall 680  (680) —  Trade name – Jake Marshall 1,150  (342) 808  Trade name – ACME 400  (18) 382  Total amortized intangible assets 12,910  (6,284) 6,626  Unamortized intangible assets: Trade name – Limbach(1) 9,960  —  9,960  Total unamortized intangible assets 9,960  —  9,960  Total amortized and unamortized assets, excluding goodwill $ 22,870  $ (6,284) $ 16,586  (1)    The Company has determined that its trade name has an indefinite useful life. The Limbach trade name has been in existence since the Company’s founding in 1901 and therefore is an established brand within the industry. (in thousands) Gross carrying amount Accumulated amortization Net intangible assets, excluding goodwill December 31, 2022       Amortized intangible assets:       Customer relationships – GCR – Jake Marshall $ 570  $ (87) $ 483  Customer relationships – ODR – Jake Marshall 3,050  (436) 2,614  Customer relationships – ODR – Limbach 4,710  (3,765) 945  Favorable leasehold interests – Limbach 190  (97) 93  Backlog – GCR – Jake Marshall 260  (178) 82  Backlog – ODR – Jake Marshall 680  (465) 215  Trade name – Jake Marshall 1,150  (202) 948  Total amortized intangible assets 10,610  (5,230) 5,380  Unamortized intangible assets: Trade name – Limbach 9,960  —  9,960  Total unamortized intangible assets 9,960  —  9,960  Total amortized and unamortized assets, excluding goodwill $ 20,570  $ (5,230) $ 15,340

v3.23.3

Debt (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Schedule of Long-Term Debt	Long-term debt consists of the following obligations as of: (in thousands) September 30, 2023 December 31, 2022 A&R Wintrust Term Loan - term loan payable in quarterly installments of principal, plus interest through February 2026 —  21,453  Wintrust Revolving Loans 10,000  —  Finance leases – collateralized by vehicles, payable in monthly installments of principal, plus interest ranging from 3.96% to 8.60% through 2027 6,949  4,954  Financing liability 5,351  5,351  Total debt 22,300  31,758  Less - Current portion of long-term debt (2,472) (9,564) Less - Unamortized discount and debt issuance costs (391) (666) Long-term debt $ 19,437  $ 21,528
Schedule of Additional Margin and Commitment Fees Payable	The following is a summary of the applicable margin and commitment fees payable on the Second A&R Wintrust Revolving Loan credit commitment: Level Senior Leverage Ratio Applicable Margin for SOFR Revolver loans Applicable Margin for Prime Revolving loans Applicable Margin for commitment fee I Greater than 1.00 to 1.00 3.10  % —  % 0.25  % II Less than or equal to 1.00 to 1.00 2.60  % (0.50) % 0.25  %

v3.23.3

Equity (Tables)	9 Months Ended
	Sep. 30, 2023
Equity [Abstract]
Schedule of Outstanding Warrants	The following table summarizes the underlying shares of common stock with respect to outstanding warrants: September 30, 2023 December 31, 2022 $15 Exercise Price Sponsor Warrants(1)(2) —  600,000  Merger Warrants(3)(4) —  629,643     Total —  1,229,643  (1)    Exercisable for one share of common stock at an exercise price of $15.00 per share (“$15 Exercise Price Sponsor Warrants”). (2)    Issued under a warrant agreement dated July 15, 2014, between Continental Stock Transfer and Trust Company, as warrant agent, and the Company. (3)    Exercisable for one share of common stock at an exercise price of $12.50 per share (“Merger Warrants”). (4)    Issued to the sellers of LHLLC.

v3.23.3

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Fair Value Measurements, Nonrecurring	Fair Value at Reporting Date Using (in thousands) September 30, 2023 Level 1 Level 2 Level 3 Cash equivalents: Overnight repurchase agreements $ 41,687  $ 41,687  U.S. Treasury Bills 10,000  10,000  $ —  $ —  Money market fund 3,750  3,750  —  —  Total $ 55,437  $ 55,437  $ —  $ —  The following table presents the carrying values of the Company's contingent earnout payment obligations included in the accompanying condensed consolidated balance sheets, which approximated fair value at September 30, 2023 and December 31, 2022. Fair Value at Reporting Date Using (in thousands) September 30, 2023 Level 1 Level 2 Level 3 Accrued expenses and other current liabilities: 2023 Jake Marshall Earnout Period $ 2,838  $ —  $ —  $ 2,838  First ACME Earnout Period 12  —  —  12  Other long-term liabilities: Second ACME Earnout Period 1,109  —  —  1,109  Total $ 3,959  $ —  $ —  $ 3,959  Fair Value at Reporting Date Using December 31, 2022 Level 1 Level 2 Level 3 Accrued expenses and other current liabilities: 2022 Jake Marshall Earnout Period (1) $ 2,859  $ —  $ —  $ 2,859  Other long-term liabilities: —  2023 Jake Marshall Earnout Period 2,515  —  —  2,515  Total $ 5,374  $ —  $ —  $ 5,374  (1)    In April 2023, the Company made a $3.0 million payment to the former owners of JMLLC and CSLLC related to the 2022 Jake Marshall Earnout Period.

v3.23.3

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of the basic and diluted earnings per share attributable to the Company's common shareholders for the three and nine months ended September 30, 2023 and 2022: Three Months Ended September 30, Nine Months Ended September 30, (in thousands, except per share amounts) 2023 2022 2023 2022 EPS numerator:     Net income $ 7,192  $ 3,641  $ 15,505  $ 2,991  EPS denominator: Weighted average shares outstanding – basic 10,963  10,445  10,696  10,430  Impact of dilutive securities 826  245  976  165  Weighted average shares outstanding – diluted 11,789  10,690  11,672  10,595  EPS: Basic $ 0.66  $ 0.35  $ 1.45  $ 0.29  Diluted $ 0.61  $ 0.34  $ 1.33  $ 0.28
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following table summarizes the securities that were antidilutive or out-of-the-money, and therefore, were not included in the computations of diluted income per common share:   Three Months Ended September 30, Nine Months Ended September 30,   2023 2022 2023 2022 Out-of-the-money warrants (see Note 7) —  1,229,643  —  1,229,643  Service-based RSUs (See Note 14) —  56  49  3,818  Performance and market-based RSUs(1) —  197  153  842  Employee Stock Purchase Plan 33  233  1,114  1,301  Total 33  1,230,129  1,316  1,235,604  (1)    For the three and nine months ended September 30, 2022, certain MRSU awards (each defined in Note 14) were not included in the computation of diluted income per common share because the performance and market conditions were not satisfied during the periods and would not be satisfied if the reporting date was at the end of the contingency period.

v3.23.3

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Schedule of Income Tax Provision (Benefit)	The following table presents our income tax provision and our income tax rate for the three and nine months ended September 30, 2023 and 2022. Three Months Ended September 30, Nine Months Ended September 30, (in thousands, except percentages) 2023 2022 2023 2022 Income tax provision $ 2,760  $ 1,654  $ 5,407  $ 1,275  Income tax rate 27.7  % 31.2  % 25.9  % 29.9  %

v3.23.3

Operating Segments (Tables)	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Schedule of Condensed Consolidated Segment Information	Condensed consolidated segment information for the three and nine months ended September 30, 2023 and 2022 were as follows:   Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2023 2022 2023 2022 Statement of Operations Data:     Revenue:     GCR $ 61,936  $ 62,653  $ 190,329  $ 200,921  ODR 65,832  59,704  183,330  152,378  Total revenue 127,768  122,357  373,659  353,299  Gross profit: GCR 11,970  9,648  33,560  26,700  ODR 19,274  15,206  52,424  37,814  Total gross profit 31,244  24,854  85,984  64,514  Selling, general and administrative(1) 20,967  18,688  62,433  56,113  Change in fair value of contingent consideration 161  386  464  1,151  Amortization of intangibles 288  386  1,054  1,184  Operating income $ 9,828  $ 5,394  $ 22,033  $ 6,066  Less unallocated amounts: Interest expense (437) (547) (1,615) (1,511) Interest income 377  —  624  —  Gain on disposition of property and equipment 68  150  28  262  Loss on early termination of operating lease —  —  —  (849) Loss on early debt extinguishment —  —  (311) —  Gain on change in fair value of interest rate swap 116  298  153  298  Total unallocated amounts 124  (99) (1,121) (1,800) Income before income taxes $ 9,952  $ 5,295  $ 20,912  $ 4,266  (1)    Included within selling, general and administrative expenses was $1.1 million and $0.8 million of stock based compensation expense for the three months ended September 30, 2023 and 2022, respectively. For the nine months ended September 30, 2023 and 2022, selling, general and administrative expenses included $3.4 million and $2.0 million of stock based compensation expenses, respectively.

v3.23.3

Leases (Tables)	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Schedule of Supplemental Balance Sheets Information	The following table summarizes the lease amounts included in the Company's condensed consolidated balance sheets: (in thousands) Classification on the Condensed Consolidated Balance Sheets September 30, 2023 December 31, 2022 Assets Operating Operating lease right-of-use assets(1) $ 15,845  $ 18,288  Finance Property and equipment, net(2)(3) 9,217  7,402  Total lease assets $ 25,062  $ 25,690  Liabilities Current    Operating Current operating lease liabilities $ 3,562  $ 3,562     Finance Current portion of long-term debt 2,472  2,135  Noncurrent    Operating Long-term operating lease liabilities 13,240  15,643     Finance Long-term debt(4) 9,828  8,170  Total lease liabilities $ 29,102  $ 29,510  (1)     Operating lease assets are recorded net of accumulated amortization of $13.0 million at September 30, 2023 and $12.2 million at December 31, 2022. (2)    Finance lease vehicle assets are recorded net of accumulated amortization of $4.9 million at September 30, 2023 and $6.0 million at December 31, 2022. (3)    Includes approximately $2.5 million and $2.6 million of net property assets associated with the Company's Pontiac Facility as of September 30, 2023 and December 31, 2022, respectively. (4)    Includes approximately $5.4 million associated with the Company's sale and leaseback financing transaction. See Note 6 for further detail.
Schedule of Lease Costs, Lease Terms and Discount Rates	The following table summarizes the lease costs included in the Company's condensed consolidated statements of operations for the three and nine months ended September 30, 2023 and 2022: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) Classification on the Condensed Consolidated Statement of Operations 2023 2022 2023 2022 Operating lease cost Cost of revenue(1) $ 543  $ 654  $ 1,626  $ 2,005  Operating lease cost Selling, general and administrative(1) 635  622  1,892  1,957  Finance lease cost    Amortization Cost of revenue(2) 714  684  2,012  2,020     Interest Interest expense, net(2) 113  68  265  200  Total lease cost $ 2,005  $ 2,028  $ 5,795  $ 6,182  (1)    Operating lease costs recorded in cost of revenue included $0.1 million and $0.2 million of variable lease costs for the three months ended September 30, 2023 and 2022, respectively, and $0.3 million and $0.4 million for the nine months ended September 30, 2023 and 2022, respectively. In addition, $0.2 million of variable lease costs are included in selling, general and administrative for each of the three months ended September 30, 2023 and 2022, and $0.4 million for each of the nine months ended September 30, 2023 and 2022. These variable costs consist of the Company's proportionate share of operating expenses, real estate taxes and utilities. (2)     Finance lease costs recorded in cost of revenue include variable lease costs of $0.9 million and $1.0 million for the three months ended September 30, 2023 and 2022, respectively, and $2.7 million and $2.8 million for the nine months ended September 30, 2023 and 2022, respectively. These variable lease costs consist of fuel, maintenance, and sales tax charges. The following is a summary of the lease terms and discount rates as of: September 30, 2023 December 31, 2022 Weighted average lease term (in years):    Operating 6.50 6.98    Finance (1) 3.12 2.73 Weighted average discount rate:    Operating 4.91  % 4.76  %    Finance (1) 6.66  % 5.06  % (1)     Excludes the weighted average lease term and weighted average discount rate associated with the aforementioned sale-leaseback financing transaction, which has a Primary Term of 25 years and utilized an implicit rate of 11.11%. See Note 6 for further detail.
Schedule of Future Minimum Commitment for Finance Leases	The future undiscounted minimum finance lease payments, as reconciled to the discounted minimum lease obligation indicated on the Company’s condensed consolidated balance sheets within current and long-term debt, less interest, and under current and long-term operating leases, less imputed interest, as of September 30, 2023 were as follows (in thousands): Finance Lease Obligations Operating Lease Obligations Year ending: Vehicles Pontiac Facility Total Finance Non-Related Party Related Party(1) Total Operating Sublease Receipts(2) Remainder of 2023 $ 813  $ 128  $ 941  $ 1,347  $ 218  $ 1,565  $ 224  2024 2,624  515  3,139  3,322  666  3,988  912  2025 2,083  528  2,611  2,787  450  3,237  939  2026 1,567  542  2,109  2,670  450  3,120  967  2027 636  555  1,191  1,693  540  2,233  326  Thereafter —  14,302  14,302  1,536  4,275  5,811  —  Total minimum lease payments 7,723  16,570  24,293  13,355  6,599  19,954  $ 3,369  Financing Component (3) (774) (11,219) (11,993) (1,676) (1,476) (3,152) Net present value of minimum lease payments 6,949  5,351  12,300  11,679  5,123  16,802  Less: current portion of finance and operating lease obligations (2,472) —  (2,472) (3,111) (451) (3,562) Long-term finance and operating lease obligations $ 4,477  $ 5,351  $ 9,828  $ 8,568  $ 4,672  $ 13,240  (1)    Associated with the aforementioned related party leases entered into with former members of JMLLC and ACME. (2)    Associated with the aforementioned third party sublease. (3)     The financing component for finance lease obligations represents the interest component of finance leases that will be recognized as interest expense in future periods. The financing component for operating lease obligations represents the effect of discounting the lease payments to their present value.
Schedule of Future Minimum Commitment for Operating Leases	The future undiscounted minimum finance lease payments, as reconciled to the discounted minimum lease obligation indicated on the Company’s condensed consolidated balance sheets within current and long-term debt, less interest, and under current and long-term operating leases, less imputed interest, as of September 30, 2023 were as follows (in thousands): Finance Lease Obligations Operating Lease Obligations Year ending: Vehicles Pontiac Facility Total Finance Non-Related Party Related Party(1) Total Operating Sublease Receipts(2) Remainder of 2023 $ 813  $ 128  $ 941  $ 1,347  $ 218  $ 1,565  $ 224  2024 2,624  515  3,139  3,322  666  3,988  912  2025 2,083  528  2,611  2,787  450  3,237  939  2026 1,567  542  2,109  2,670  450  3,120  967  2027 636  555  1,191  1,693  540  2,233  326  Thereafter —  14,302  14,302  1,536  4,275  5,811  —  Total minimum lease payments 7,723  16,570  24,293  13,355  6,599  19,954  $ 3,369  Financing Component (3) (774) (11,219) (11,993) (1,676) (1,476) (3,152) Net present value of minimum lease payments 6,949  5,351  12,300  11,679  5,123  16,802  Less: current portion of finance and operating lease obligations (2,472) —  (2,472) (3,111) (451) (3,562) Long-term finance and operating lease obligations $ 4,477  $ 5,351  $ 9,828  $ 8,568  $ 4,672  $ 13,240  (1)    Associated with the aforementioned related party leases entered into with former members of JMLLC and ACME. (2)    Associated with the aforementioned third party sublease. (3)     The financing component for finance lease obligations represents the interest component of finance leases that will be recognized as interest expense in future periods. The financing component for operating lease obligations represents the effect of discounting the lease payments to their present value.
Schedule of Leases Supplemental Cash Flow Information	The following is a summary of other information and supplemental cash flow information related to finance and operating leases: Nine months ended September 30, (in thousands) 2023 2022 Cash paid for amounts included in the measurement of lease liabilities:    Operating cash flows from operating leases $ 3,478  $ 3,890     Operating cash flows from finance leases 227  200     Financing cash flows from finance leases 2,032  2,051  Right-of-use assets exchanged for lease liabilities:    Operating leases 1,043  —     Finance leases 4,062  2,171  Right-of-use assets disposed or adjusted modifying operating leases liabilities (643) 2,396  Right-of-use assets disposed or adjusted modifying finance leases liabilities $ (77) (77)

v3.23.3

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Components of Self-Insurance	The components of the self-insurance liability as of September 30, 2023 and December 31, 2022 are as follows: (in thousands) September 30, 2023 December 31, 2022 Current liability — workers’ compensation and general liability $ 99  $ 158  Current liability — medical and dental 422  557  Non-current liability 746  343  Total liability $ 1,267  $ 1,058  Restricted cash $ 65  $ 113

v3.23.3

Management Incentive Plans (Tables)	9 Months Ended
	Sep. 30, 2023
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes the Company's service-based RSU activity for the nine months ended September 30, 2023:   Awards Weighted-Average Grant Date Fair Value Unvested at December 31, 2022 280,275  $ 9.06  Granted 164,413  11.94  Vested (163,354) 8.58  Forfeited (42,131) 10.63  Unvested at September 30, 2023 239,203  $ 11.09
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes the Company's PRSU activity for the nine months ended September 30, 2023:   Awards Weighted-Average Grant Date Fair Value Unvested at December 31, 2022 497,940  $ 8.32  Granted 289,092  12.77  Performance factor adjustment(1) 32,327  4.29  Vested (121,827) 4.29  Forfeited (116,911) 9.81  Unvested at September 30, 2023 580,621  $ 10.85  (1)     Performance-based awards covering the three year period ended December 31, 2022 were paid out in the first quarter of 2023 based on the approval of the Company's Compensation Committee. The performance factor during the measurement period used to determine compensation payouts was 136.13% of the pre-defined metric target of 100%, which resulted in a positive performance factor adjustment and the issuance of 32,327 of additional awards associated with the original grant.

v3.23.3

Business and Organization (Details)	9 Months Ended
	Sep. 30, 2023 segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments	2
Service period	2 years

v3.23.3

Acquisitions - Narrative (Details) $ in Thousands			3 Months Ended		9 Months Ended
	Jul. 03, 2023 USD ($) payment	Dec. 02, 2021 USD ($) payment	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Business Acquisition [Line Items]
Goodwill associated with the ACME Transaction					$ 2,333
Amortization of intangibles			$ 288	$ 386	1,054	$ 1,184
ODR
Business Acquisition [Line Items]
Goodwill associated with the ACME Transaction					2,333
ACME Industrial piping LLC
Business Acquisition [Line Items]
Consideration paid at closing	$ 5,000
Amount of consideration paid held in escrow for indemnification purposes	400
Earnout payments	2,500		1,100		1,100
Acquisition-related expenses					300
Amortization of intangibles					100
Remainder of 2023			100		100
2024			300		300
2025			300		300
2026			300		300
2027			300		300
2028			$ 300		$ 300
ACME Industrial piping LLC | Earn Out Payment Two
Business Acquisition [Line Items]
Earnout payments	$ 2,000
Number of earnout tranches | payment	2
Earnout period	12 months
ACME Industrial piping LLC | Earn Out Payment Two | Maximum
Business Acquisition [Line Items]
Gross profits from acquired companies	$ 2,500
ACME Industrial piping LLC | Earn Out Payment One
Business Acquisition [Line Items]
Earnout payments	$ 500
Number of earnout tranches | payment	2
Earnout period	12 months
ACME Industrial piping LLC | Earn Out Payment One | Maximum
Business Acquisition [Line Items]
Gross profits from acquired companies	$ 2,000
ACME Industrial piping LLC | ODR
Business Acquisition [Line Items]
Goodwill associated with acquisition	2,300
Goodwill associated with the ACME Transaction	2,300
Jake Marshall Transaction
Business Acquisition [Line Items]
Earnout payments		$ 6,000
Jake Marshall Transaction | Level 3
Business Acquisition [Line Items]
Earnout payments	$ 1,100
Jake Marshall Transaction | Maximum | Measurement Input, Discount Rate | Level 3
Business Acquisition [Line Items]
Earnout payments, measurement input	0.1449
Jake Marshall Transaction | Minimum | Measurement Input, Discount Rate | Level 3
Business Acquisition [Line Items]
Earnout payments, measurement input	0.0865
Jake Marshall Transaction | Earn Out Payment Two
Business Acquisition [Line Items]
Earnout payments		$ 3,000
Number of earnout tranches | payment		2
Earnout period		12 months
Jake Marshall Transaction | Earn Out Payment Two | Maximum
Business Acquisition [Line Items]
Gross profits from acquired companies		$ 10,000
Jake Marshall Transaction | Earn Out Payment Two | Minimum
Business Acquisition [Line Items]
Gross profits from acquired companies		8,000
Jake Marshall Transaction | Earn Out Payment One
Business Acquisition [Line Items]
Earnout payments		$ 3,000
Number of earnout tranches | payment		2
Earnout period		12 months
Jake Marshall Transaction | Earn Out Payment One | Maximum
Business Acquisition [Line Items]
Gross profits from acquired companies		$ 10,000
Jake Marshall Transaction | Earn Out Payment One | Minimum
Business Acquisition [Line Items]
Gross profits from acquired companies		$ 8,000

v3.23.3

Acquisitions - Allocation of Purchase Price of Assets and Liabilities from Jake Marshall Transaction (Details) - USD ($) $ in Thousands	Jul. 03, 2023	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair value of liabilities assumed:
Goodwill		$ 13,703	$ 11,370	$ 11,370
ACME Industrial piping LLC
Consideration:
Cash	$ 5,181
Earnout provision	1,121
Total Consideration	6,302
Fair value of assets acquired:
Cash and cash equivalents	298
Accounts receivable	1,150
Contract assets	414
Property and equipment	488
Operating lease right-of-use assets	301
Intangible assets	2,300
Amount attributable to assets acquired	4,951
Fair value of liabilities assumed:
Accounts payable, including retainage	170
Current operating lease liabilities	195
Accrued expenses and other current liabilities	138
Contract liabilities	373
Long-term operating lease liabilities	106
Amount attributable to liabilities assumed	982
Goodwill	$ 2,333

v3.23.3

Acquisitions - Intangible Assets, Net (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Business Acquisition [Line Items]
Gross Carrying Amount	$ 12,910	$ 10,610
Accumulated Amortization	(6,284)	(5,230)
Net Intangible Assets	6,626	$ 5,380
ACME Industrial piping LLC
Business Acquisition [Line Items]
Gross Carrying Amount	2,300
Accumulated Amortization	(64)
Net Intangible Assets	$ 2,236
Weighted Average Useful Life (Years)	6 years 3 months 18 days
Trade name and trademarks | ACME Industrial piping LLC
Business Acquisition [Line Items]
Gross Carrying Amount	$ 400
Accumulated Amortization	(18)
Net Intangible Assets	$ 382
Weighted Average Useful Life (Years)	5 years 6 months
Customer relationships | ACME Industrial piping LLC
Business Acquisition [Line Items]
Gross Carrying Amount	$ 1,900
Accumulated Amortization	(46)
Net Intangible Assets	$ 1,854
Weighted Average Useful Life (Years)	10 years 3 months 18 days

v3.23.3

Revenue from Contracts with Customers - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($) project	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) project	Sep. 30, 2022 USD ($) project	Dec. 31, 2022 USD ($)
Disaggregation of Revenue [Line Items]
Term of revenue contracts			three months to two years
Percentage completed of certain milestones			10.00%
Net amount of unresolved change orders and claims	$ 19.7		$ 19.7		$ 28.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligations, expected timing of satisfaction, period	24 months		24 months
GCR
Disaggregation of Revenue [Line Items]
Number of projects with write downs | project	3		2
Revision amount for gross profit impact on contract estimates (more than)		$ 0.5
Number of projects subject to gross profit write down | project	1		1	2
Total gross profits adjustments net	$ 3.1		$ 2.2	$ 2.0
Write-up settlement	1.2		1.2
Total gross profits adjustments, write downs	0.7		0.5	$ 1.1
GCR | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Disaggregation of Revenue [Line Items]
Remaining performance obligations, amount	$ 227.0		$ 227.0
Revenue, remaining performance obligations, percentage	27.00%		27.00%
Revenue, remaining performance obligations, expected timing of satisfaction, period	3 months		3 months
GCR | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligations, percentage	48.00%		48.00%
Revenue, remaining performance obligations, expected timing of satisfaction, period	1 year		1 year
ODR
Disaggregation of Revenue [Line Items]
Number of projects subject to gross profit write down | project	1		1
Total gross profits adjustments, write downs	$ 0.6		$ 0.7
ODR | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Disaggregation of Revenue [Line Items]
Remaining performance obligations, amount	$ 138.1		$ 138.1
Revenue, remaining performance obligations, percentage	48.00%		48.00%
Revenue, remaining performance obligations, expected timing of satisfaction, period	3 months		3 months
ODR | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligations, percentage	35.00%		35.00%
Revenue, remaining performance obligations, expected timing of satisfaction, period	1 year		1 year

v3.23.3

Revenue from Contracts with Customers - Schedule of Components of Contract Asset and Liability Balances (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Contract assets
Costs and estimated earnings in excess of billings on uncompleted contracts	$ 26,007	$ 33,573
Retainage receivable	21,846	27,880
Total contract assets	47,853	61,453
Change in costs in excess of billings and estimated earnings	(7,566)
Change in retainage receivable	(6,034)
Change in total contract assets	(13,600)
Contract liabilities
Billings in excess of costs and estimated earnings on uncompleted contracts	46,545	43,806
Provisions for losses	147	201
Total contract liabilities	46,692	$ 44,007
Change in billings in excess of costs and estimated earnings	2,739
Change in provisions for losses	(54)
Change in total contract liabilities	$ 2,685

v3.23.3

Revenue from Contracts with Customers - Schedule of Contracts In Progress (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Revenue earned on uncompleted contracts	$ 625,765	$ 678,014
Less: Billings to date	(646,303)	(688,247)
Net (overbilling) underbilling	(20,538)	(10,233)
Costs in excess of billings and estimated earnings on uncompleted contracts	26,007	33,573
Billings in excess of costs and estimated earnings on uncompleted contracts	$ (46,545)	$ (43,806)

v3.23.3

Goodwill and Intangibles - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 13,703,000		$ 13,703,000		$ 11,370,000	$ 11,370,000
Impairment of intangible assets (excluding goodwill)	0	$ 0	0	$ 0
Amortization of intangibles	$ 288,000	$ 386,000	$ 1,054,000	$ 1,184,000

v3.23.3

Goodwill and Intangibles - Carrying Amount of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($)
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 11,370
Goodwill associated with the ACME Transaction	2,333
Goodwill, Ending Balance	13,703
GCR
Goodwill [Roll Forward]
Goodwill, Beginning Balance	0
Goodwill associated with the ACME Transaction	0
Goodwill, Ending Balance	0
ODR
Goodwill [Roll Forward]
Goodwill, Beginning Balance	11,370
Goodwill associated with the ACME Transaction	2,333
Goodwill, Ending Balance	$ 13,703

v3.23.3

Goodwill and Intangibles - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Amortized intangible assets:
Gross carrying amount	$ 12,910	$ 10,610
Accumulated Amortization	(6,284)	(5,230)
Net intangible assets, excluding goodwill	6,626	5,380
Unamortized intangible assets:
Gross carrying amount	9,960	9,960
Net intangible assets, excluding goodwill	9,960	9,960
Gross carrying amount	22,870	20,570
Accumulated Amortization	(6,284)	(5,230)
Total amortized and unamortized assets, excluding goodwill	16,586	15,340
ACME Industrial piping LLC
Amortized intangible assets:
Gross carrying amount	2,300
Accumulated Amortization	(64)
Net intangible assets, excluding goodwill	2,236
Unamortized intangible assets:
Accumulated Amortization	(64)
Trade name
Unamortized intangible assets:
Gross carrying amount	9,960	9,960
Net intangible assets, excluding goodwill	9,960	9,960
Customer relationships | ACME Industrial piping LLC
Amortized intangible assets:
Gross carrying amount	1,900
Accumulated Amortization	(46)
Net intangible assets, excluding goodwill	1,854
Unamortized intangible assets:
Accumulated Amortization	(46)
Customer relationships | GCR | Jake Marshall Transaction
Amortized intangible assets:
Gross carrying amount	570	570
Accumulated Amortization	(148)	(87)
Net intangible assets, excluding goodwill	422	483
Unamortized intangible assets:
Accumulated Amortization	(148)	(87)
Customer relationships | ODR
Amortized intangible assets:
Gross carrying amount	4,710	4,710
Accumulated Amortization	(3,944)	(3,765)
Net intangible assets, excluding goodwill	766	945
Unamortized intangible assets:
Accumulated Amortization	(3,944)	(3,765)
Customer relationships | ODR | Jake Marshall Transaction
Amortized intangible assets:
Gross carrying amount	3,050	3,050
Accumulated Amortization	(737)	(436)
Net intangible assets, excluding goodwill	2,313	2,614
Unamortized intangible assets:
Accumulated Amortization	(737)	(436)
Customer relationships | ODR | ACME Industrial piping LLC
Amortized intangible assets:
Gross carrying amount	1,900
Accumulated Amortization	(46)
Net intangible assets, excluding goodwill	1,854
Unamortized intangible assets:
Accumulated Amortization	(46)
Favorable Leasehold Interests
Amortized intangible assets:
Gross carrying amount	190	190
Accumulated Amortization	(109)	(97)
Net intangible assets, excluding goodwill	81	93
Unamortized intangible assets:
Accumulated Amortization	(109)	(97)
Backlog – Construction | GCR | Jake Marshall Transaction
Amortized intangible assets:
Gross carrying amount	260	260
Accumulated Amortization	(260)	(178)
Net intangible assets, excluding goodwill	0	82
Unamortized intangible assets:
Accumulated Amortization	(260)	(178)
Backlog – Construction | ODR | Jake Marshall Transaction
Amortized intangible assets:
Gross carrying amount	680	680
Accumulated Amortization	(680)	(465)
Net intangible assets, excluding goodwill	0	215
Unamortized intangible assets:
Accumulated Amortization	(680)	(465)
Trade name | Jake Marshall Transaction
Amortized intangible assets:
Gross carrying amount	1,150	1,150
Accumulated Amortization	(342)	(202)
Net intangible assets, excluding goodwill	808	948
Unamortized intangible assets:
Accumulated Amortization	(342)	$ (202)
Trade name | ACME Industrial piping LLC
Amortized intangible assets:
Gross carrying amount	400
Accumulated Amortization	(18)
Net intangible assets, excluding goodwill	382
Unamortized intangible assets:
Accumulated Amortization	$ (18)

v3.23.3

Debt - Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Net present value of minimum lease payments	$ 12,300
Total debt	22,300	$ 31,758
Less - Current portion of long-term debt	(2,472)	(9,564)
Less - Unamortized discount and debt issuance costs	(391)	(666)
Long-term debt	19,437	21,528
Vehicles
Debt Instrument [Line Items]
Net present value of minimum lease payments	6,949	4,954
Pontiac Facility
Debt Instrument [Line Items]
Net present value of minimum lease payments	$ 5,351	5,351
Minimum
Debt Instrument [Line Items]
Finance lease, discount rate	3.96%
Maximum
Debt Instrument [Line Items]
Finance lease, discount rate	8.60%
Secured Debt | A&R Wintrust Term Loan - term loan payable in quarterly installments of principal, plus interest through February 2026
Debt Instrument [Line Items]
Long term debt	$ 0	21,453
Revolving Credit Facility | Wintrust Revolving Loans
Debt Instrument [Line Items]
Long term debt	$ 10,000	$ 0

v3.23.3

Debt - Wintrust Term and Revolving Loans (Details)				3 Months Ended			9 Months Ended
	Jul. 03, 2023 USD ($) covenant	May 05, 2023 USD ($) covenant	Feb. 24, 2021 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Jul. 31, 2022 USD ($)
Interest Rate Swap
Debt Instrument [Line Items]
Notional amount										$ 10,000,000
Fixed interest rate										3.12%
Wintrust Term Loan
Debt Instrument [Line Items]
Debt effective interest rate		9.25%			7.25%			7.25%
Debt weighted average annual interest rate		8.76%
Interest rate during period					6.35%			5.08%
A&R Wintrust Term And Revolving Loans
Debt Instrument [Line Items]
Number of financial covenants | covenant	3	3
Debt instrument, covenant compliance, leverage ratio	2.00	2.00
Debt instrument, covenant compliance, coverage ratio	1.20	1.20
Aggregate amount of unfinanced capital expenditures during any fiscal year	$ 0	$ 0
Limit annual percentage of unfinanced capital expenditures	50.00%	50.00%
Maximum outstanding borrowings during the period				$ 10,000,000	$ 3,500,000		$ 10,000,000	$ 9,400,000
Weighted average annual interest rate				5.72%	5.25%		5.72%	4.78%
A&R Wintrust Term And Revolving Loans | Maximum
Debt Instrument [Line Items]
Aggregate amount of unfinanced capital expenditures during any fiscal year	$ 4,000,000	$ 4,000,000
Amount drawn under credit agreement				$ 10,000,000			$ 10,000,000		$ 0
Average daily balance of borrowings outstanding				10,000,000	$ 200,000		5,500,000	$ 100,000
Wintrust Loans
Debt Instrument [Line Items]
Letters of credit				$ 4,200,000			$ 4,200,000
Secured Debt | Wintrust Term Loan
Debt Instrument [Line Items]
Debt issued		50,000,000	$ 30,000,000
Debt installment payments			$ 500,000
Secured Debt | A&R Wintrust Term Loan
Debt Instrument [Line Items]
Debt installment payments	$ 600,000
Annual excess cash flow payments credit agreement period	120 days
Excess cash flow payments						$ 3,300,000
Net claim proceeds payments					$ 600,000	$ 2,100,000
Secured Debt | A&R Wintrust Term Loan | Jake Marshall Transaction
Debt Instrument [Line Items]
Debt issued	$ 35,500,000
Secured Debt | Revolving Credit Facility | Wintrust Revolving Loans | Jake Marshall Transaction
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	25,000,000
Secured Debt | Sublimit for Letters of Credit | Wintrust Revolving Loans | Jake Marshall Transaction
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 5,000,000	5,000,000
Line of Credit | A&R Wintrust Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Step-down adjustment on basis spread on variable rate	0.75%
Line of Credit | A&R Wintrust Term Loan | Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Line of Credit | A&R Wintrust Term Loan | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Step-down adjustment on basis spread on variable rate	0.50%
Line of Credit | A&R Wintrust Term Loan | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Variable Rate Component One
Debt Instrument [Line Items]
Basis spread on variable rate	4.10%
Line of Credit | A&R Wintrust Term Loan | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Variable Rate Component Two
Debt Instrument [Line Items]
Basis spread on variable rate	4.26%
Line of Credit | A&R Wintrust Term Loan | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Variable Rate Component Three
Debt Instrument [Line Items]
Basis spread on variable rate	4.42%
Line of Credit | A&R Wintrust Term Loan | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.15%
Line of Credit | Revolving Credit Facility | Wintrust Term Loan | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Step-down adjustment on basis spread on variable rate			0.50%
Line of Credit | Revolving Credit Facility | Wintrust Term Loan | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			0.25%
Line of Credit | Revolving Credit Facility | Wintrust Term Loan | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			4.00%
Line of Credit | Revolving Credit Facility | Wintrust Term Loan | Base Rate
Debt Instrument [Line Items]
Step-down adjustment on basis spread on variable rate			0.75%
Line of Credit | Revolving Credit Facility | Wintrust Term Loan | Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			3.00%
Line of Credit | Revolving Credit Facility | Wintrust Term Loan | Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		25,000,000	$ 25,000,000
Outstanding balance		9,600,000
Unamortized debt issuance costs		$ 300,000
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			0.25%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			3.50%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Step-down adjustment on basis spread on variable rate	0.50%	0.50%	0.50%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%	3.00%	3.00%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Variable Rate Component One
Debt Instrument [Line Items]
Basis spread on variable rate	3.60%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Variable Rate Component Two
Debt Instrument [Line Items]
Basis spread on variable rate	3.76%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Variable Rate Component Three
Debt Instrument [Line Items]
Basis spread on variable rate	3.92%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.15%	0.15%
Line of Credit | Revolving Credit Facility | Wintrust Revolving Loans | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		3.10%
Line of Credit | Sublimit for Letters of Credit | Wintrust Revolving Loans
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 5,000,000

v3.23.3

Debt - Additional Margin and Commitment Fees Payable (Details)	9 Months Ended
	Sep. 30, 2023
Level I
Debt Instrument [Line Items]
Senior Leverage Ratio	100.00%
Level I | Wintrust Revolving Loans
Debt Instrument [Line Items]
Additional margin for loans	0.25%
Level I | Secured Overnight Financing Rate (SOFR) | Wintrust Revolving Loans
Debt Instrument [Line Items]
Additional margin for loans	3.10%
Level I | Prime Rate | Wintrust Revolving Loans
Debt Instrument [Line Items]
Additional margin for loans	0.00%
Level II
Debt Instrument [Line Items]
Senior Leverage Ratio	100.00%
Level II | Wintrust Revolving Loans
Debt Instrument [Line Items]
Additional margin for loans	0.25%
Level II | Secured Overnight Financing Rate (SOFR) | Wintrust Revolving Loans
Debt Instrument [Line Items]
Additional margin for loans	2.60%
Level II | Prime Rate | Wintrust Revolving Loans
Debt Instrument [Line Items]
Additional margin for loans	(0.50%)

v3.23.3

Debt - Sale-Leaseback Financing Transactions (Details)		3 Months Ended	9 Months Ended
	Sep. 29, 2022 USD ($) renewalTerm	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Disclosure [Abstract]
Purchase of property under sale and leaseback transaction	$ 7,800,000	$ 2,500,000	$ 2,500,000	$ 2,600,000
Purchase price	5,400,000
Tenant improvement allowance	$ 2,400,000
Lease agreement, term	25 years
Lease agreement, number of renewal terms | renewalTerm	2
Lease agreement, renewal term	5 years
Sale leaseback transaction, annual minimum rent	$ 499,730
Annual increase rate	2.50%
Termination fee	$ 1,700,000
Discount rate	11.11%
Tenant Improvement Allowance, implicit rate	6.53%
Sale leaseback transaction, gain or loss recognized			0
Finance lease liability		4,900,000	4,900,000
Financing interest expense		$ 100,000	$ 400,000

v3.23.3

Equity - Narrative (Details) - USD ($)					1 Months Ended				3 Months Ended	9 Months Ended
	Jul. 20, 2023	Mar. 29, 2023	Mar. 25, 2022	Jan. 01, 2020	Jul. 31, 2023	Jan. 31, 2023	Jul. 31, 2022	Jan. 31, 2022	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Class of Stock [Line Items]
Common stock, shares authorized (in shares)										100,000,000	100,000,000
Common stock, par or stated value per share (in usd per share)										$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)										1,000,000
Preferred stock, par or stated value per share (in usd per shares)										$ 0.0001
Class of warrant or right, outstanding (in shares)										0	1,229,643
Share Repurchase Program
Class of Stock [Line Items]
Repurchase of common stock												$ 2,000,000
Number of shares acquired (in shares)										2,000,000
2022 Amended And Restated Omnibus Incentive Plan
Class of Stock [Line Items]
Number of additional shares authorized under share-based compensation plan (in shares)			350,000
Common stock, capital shares reserved for future issuance (in shares)			2,600,000
2023 Amended And Restated Omnibus Incentive Plan
Class of Stock [Line Items]
Number of additional shares authorized under share-based compensation plan (in shares)		450,000
Common stock, capital shares reserved for future issuance (in shares)		3,050,000
ESPP | Employee Stock Purchase Plan
Class of Stock [Line Items]
Purchase price of common stock, percent of market price (no less than)				85.00%
Maximum employee subscription percentage				10.00%
Maximum contribution amount				$ 5,000
Offering period				6 months
Discount percentage from market price, beginning of purchase period				15.00%
Award vesting period				6 months
Number of shares authorized (in shares)				500,000
Shares issued (in shares)					6,664	10,997	24,592	12,898
Shares remaining available for future issuance (in shares)										388,956
$15 Exercise Price Sponsor Warrants
Class of Stock [Line Items]
Exercise price of warrants (in usd per share)										$ 15.00	$ 15
Warrants redeemed (in shares)									600,000
Class of warrant or right, outstanding (in shares)										0	600,000
Merger Warrants
Class of Stock [Line Items]
Exercise price of warrants (in usd per share)										$ 12.50	$ 12.50
Warrants redeemed (in shares)	443,032								163,444
Warrant converted into securities (in shares)	228,945									45,797
Class of warrant or right, outstanding (in shares)										0	629,643
Sponsor Warrant
Class of Stock [Line Items]
Warrant converted into securities (in shares)										167,564
unexercised Merger Warrants
Class of Stock [Line Items]
Class of warrant or right, outstanding (in shares)	23,167

v3.23.3

Equity - Schedule of Outstanding Warrants (Details) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Class of warrant or right, outstanding (in shares)	0	1,229,643
$15 Exercise Price Sponsor Warrants
Class of Stock [Line Items]
Class of warrant or right, outstanding (in shares)	0	600,000
Class of warrant or right, number of securities called by each warrant or right (in shares)	1	1
Exercise price of warrants (in usd per share)	$ 15.00	$ 15
Merger Warrants
Class of Stock [Line Items]
Class of warrant or right, outstanding (in shares)	0	629,643
Class of warrant or right, number of securities called by each warrant or right (in shares)	1	1
Exercise price of warrants (in usd per share)	$ 12.50	$ 12.50

v3.23.3

Fair Value Measurements - Narrative (Details) $ in Thousands			1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 03, 2023 USD ($) payment	Dec. 02, 2021 USD ($) payment	Apr. 30, 2023 USD ($)	Sep. 30, 2023 USD ($) approach	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) approach	Sep. 30, 2022 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest income				$ 377	$ 0	$ 624	$ 0
Payment to former owners			$ 3,000
Change in fair value of contingent consideration				161	386	464	1,151
Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain on change in fair value of interest rate swap				100	300	200	300
Other Long-term Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of the interest rate swap				500		500
Jake Marshall Transaction
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments		$ 6,000
Change in fair value of contingent consideration				200	$ 400	500	$ 1,200
Jake Marshall Transaction | Earn Out Payment Two
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments		$ 3,000
Number of earnout tranches | payment		2
Earnout period		12 months
Jake Marshall Transaction | Earn Out Payment One
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments		$ 3,000
Number of earnout tranches | payment		2
Earnout period		12 months
Jake Marshall Transaction | Maximum | Earn Out Payment Two
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross profits from acquired companies		$ 10,000
Jake Marshall Transaction | Maximum | Earn Out Payment One
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross profits from acquired companies		10,000
Jake Marshall Transaction | Minimum | Earn Out Payment Two
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross profits from acquired companies		8,000
Jake Marshall Transaction | Minimum | Earn Out Payment One
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross profits from acquired companies		8,000
ACME Industrial piping LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments	$ 2,500			1,100		1,100
ACME Industrial piping LLC | Earn Out Payment Two
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments	$ 2,000
Number of earnout tranches | payment	2
Earnout period	12 months
ACME Industrial piping LLC | Earn Out Payment One
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments	$ 500
Number of earnout tranches | payment	2
Earnout period	12 months
ACME Industrial piping LLC | Maximum | Earn Out Payment Two
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross profits from acquired companies	$ 2,500
ACME Industrial piping LLC | Maximum | Earn Out Payment One
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross profits from acquired companies	2,000
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest income				$ 400		$ 600
Level 3 | Jake Marshall Transaction
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments	$ 1,100
Level 3 | Jake Marshall Transaction | Measurement Input, Discount Rate | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments, measurement input	0.1449
Level 3 | Jake Marshall Transaction | Measurement Input, Discount Rate | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments, measurement input	0.0865
Level 3 | Contingent Consideration Liability | Jake Marshall Transaction
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of earnout payments		$ 3,100
Level 3 | Contingent Consideration Liability | ACME Industrial piping LLC | Measurement Input, Discount Rate | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments, measurement input | approach				0.1449		0.1449
Level 3 | Contingent Consideration Liability | ACME Industrial piping LLC | Measurement Input, Discount Rate | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout payments, measurement input | approach				0.0865		0.0865
Wintrust Term Loan | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of debt				$ 10,000		$ 10,000

v3.23.3

Fair Value Measurements - Schedule of Cash and Cash Equivalents (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 55,437
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	55,437
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	0
Overnight repurchase agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	41,687
Overnight repurchase agreements | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	41,687
Overnight repurchase agreements | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total
Overnight repurchase agreements | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total
U.S. Treasury Bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	10,000
U.S. Treasury Bills | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	10,000
U.S. Treasury Bills | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	0
U.S. Treasury Bills | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	0
Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	3,750
Money market fund | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	3,750
Money market fund | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	0
Money market fund | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 0

v3.23.3

Fair Value Measurements - Carrying Values of the Company's Contingent Earnout Payment Obligations (Details) - USD ($) $ in Thousands	1 Months Ended
	Apr. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		$ 3,959	$ 5,374
Payment to former owners	$ 3,000
Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		0	0
Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		0	0
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		3,959	5,374
2023 Jake Marshall Earnout Period
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		2,838
Other long-term liabilities:			2,515
2023 Jake Marshall Earnout Period | Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		0
Other long-term liabilities:			0
2023 Jake Marshall Earnout Period | Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		0
Other long-term liabilities:			0
2023 Jake Marshall Earnout Period | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		2,838
Other long-term liabilities:			2,515
2022 Jake Marshall Earnout Period
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:			2,859
2022 Jake Marshall Earnout Period | Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:			0
2022 Jake Marshall Earnout Period | Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:			0
2022 Jake Marshall Earnout Period | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:			$ 2,859
First ACME Earnout Period
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		12
First ACME Earnout Period | Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		0
First ACME Earnout Period | Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		0
First ACME Earnout Period | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued expenses and other current liabilities:		12
Second ACME Earnout Period
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		1,109
Second ACME Earnout Period | Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		0
Second ACME Earnout Period | Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		0
Second ACME Earnout Period | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other long-term liabilities:		$ 1,109

v3.23.3

Earnings per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
EPS numerator:
Net income	$ 7,192	$ 5,320	$ 2,993	$ 3,641	$ 866	$ (1,516)	$ 15,505	$ 2,991
EPS denominator:
Weighted average shares outstanding - basic (in shares)	10,962,622			10,444,987			10,695,973	10,429,671
Impact of dilutive securities (in shares)	826,000			245,000			976,000	165,000
Weighted average shares outstanding - diluted (in shares)	11,789,137			10,690,434			11,671,819	10,595,061
EPS:
Basic (in usd per share)	$ 0.66			$ 0.35			$ 1.45	$ 0.29
Diluted (in usd per share)	$ 0.61			$ 0.34			$ 1.33	$ 0.28

v3.23.3

Earnings per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	33	1,230,129	1,316	1,235,604
Out-of-the money warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0	1,229,643	0	1,229,643
Service-based RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0	56	49	3,818
Performance and market-based RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0	197	153	842
Employee Stock Purchase Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	33	233	1,114	1,301

v3.23.3

Income Taxes (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income tax provision	$ 2,760,000	$ 1,654,000	$ 5,407,000	$ 1,275,000
Income tax rate	27.70%	31.20%	25.90%	29.90%
Valuation allowance	$ 0		$ 0		$ 0

v3.23.3

Operating Segments - Narrative (Details)	9 Months Ended
	Sep. 30, 2023 segment
Segment Reporting Information [Line Items]
Number of operating segments	2
GCR
Segment Reporting Information [Line Items]
Number of reportable segments	1
ODR
Segment Reporting Information [Line Items]
Number of reportable segments	1

v3.23.3

Operating Segments - Schedule of Condensed Consolidated Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Revenue	$ 127,768	$ 122,357	$ 373,659	$ 353,299
Total gross profit	31,244	24,854	85,984	64,514
Selling, general and administrative	20,967	18,688	62,433	56,113
Change in fair value of contingent consideration	161	386	464	1,151
Amortization of intangibles	288	386	1,054	1,184
Operating income	9,828	5,394	22,033	6,066
Interest expense	(437)	(547)	(1,615)	(1,511)
Interest income	377	0	624	0
Gain on disposition of property and equipment	68	150	28	262
Loss on early termination of operating lease	0	0	0	(849)
Loss on early debt extinguishment	0	0	(311)	0
Gain on change in fair value of interest rate swap	116	298	153	298
Total unallocated amounts	124	(99)	(1,121)	(1,800)
Income before income taxes	9,952	5,295	20,912	4,266
Operating Segments | GCR
Segment Reporting Information [Line Items]
Revenue	61,936	62,653	190,329	200,921
Total gross profit	11,970	9,648	33,560	26,700
Operating Segments | ODR
Segment Reporting Information [Line Items]
Revenue	65,832	59,704	183,330	152,378
Total gross profit	19,274	15,206	52,424	37,814
Corporate
Segment Reporting Information [Line Items]
Selling, general and administrative	$ 1,100	$ 800	$ 3,400	$ 2,000

v3.23.3

Leases - Narrative (Details)		1 Months Ended		3 Months Ended			9 Months Ended
	Dec. 02, 2021 USD ($) extension	Mar. 31, 2022 USD ($) ft²	Jun. 30, 2021 USD ($) ft²	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Mar. 31, 2022 USD ($) ft²	Sep. 30, 2023 USD ($) extension	Sep. 30, 2022 USD ($)	Jun. 30, 2022 installment
Lessee, Lease, Description [Line Items]
Lease termination fee		$ 700,000
Lease termination fee payable, number of installments | installment									16
Gain on derecognition of lease assets and liabilities							$ 100,000
Loss on disposal of leasehold improvement							$ 100,000
Real Estate Leases
Lessee, Lease, Description [Line Items]
Number of lease extensions | extension							1
Office Building | Geographic Distribution, Domestic
Lessee, Lease, Description [Line Items]
Subleased area (in sq ft) | ft²		16,720	71,787			16,720
Sublease annual base rent			$ 600,000			$ 800,000
Sublease annual base rent increase percentage			3.00%			3.00%
Sublease income				$ 300,000	$ 200,000		$ 500,000	$ 400,000
Jake Marshall Transaction | Land and Building | Full Time Employee
Lessee, Lease, Description [Line Items]
Number of lease extensions | extension	2
Lease term	10 years
Term of lease extensions	2 years
Jake Marshall Transaction | Land and Building | Full Time Employee | Lease Contractual Term One
Lessee, Lease, Description [Line Items]
Lease term	5 years
Monthly base rent	$ 37,500
Jake Marshall Transaction | Land and Building | Full Time Employee | Lease Contractual Term Two
Lessee, Lease, Description [Line Items]
Lease term	5 years
Monthly base rent	$ 45,000
ACME Industrial piping LLC | Land and Building | Full Time Employee | Lease Contractual Term One
Lessee, Lease, Description [Line Items]
Lease term	6 months
Monthly base rent	$ 17,000
ACME Industrial piping LLC | Land and Building | Full Time Employee | Lease Contractual Term Two
Lessee, Lease, Description [Line Items]
Lease term	6 months
Monthly base rent	$ 18,000
ACME Industrial piping LLC | Land and Building | Full Time Employee | Lease Contractual Term Three
Lessee, Lease, Description [Line Items]
Monthly base rent	$ 19,000

v3.23.3

Leases - Supplemental Balance Sheets Information (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 29, 2022
Leases [Abstract]
Operating lease right-of-use assets	$ 15,845	$ 18,288
Property, plant and equipment, net	9,217	7,402
Total lease assets	25,062	25,690
Less: current portion of finance and operating lease obligations	3,562	3,562
Less: current portion of finance and operating lease obligations	2,472	2,135
Long-term finance and operating lease obligations	13,240	15,643
Long-term finance and operating lease obligations	9,828	8,170
Total lease liabilities	29,102	29,510
Operating lease, accumulated amortization	13,000	12,200
Finance lease, accumulated amortization	4,900	6,000
Purchase of property under sale and leaseback transaction	2,500	$ 2,600	$ 7,800
Financing liability	$ 5,400
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Long-Term Debt and Lease Obligation, Current	Long-Term Debt and Lease Obligation, Current
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt	Long-term debt

v3.23.3

Leases - Summary of Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Lessee, Lease, Description [Line Items]
Finance lease cost, amortization	$ 714	$ 684	$ 2,012	$ 2,020
Finance lease cost, interest expense	113	68	265	200
Total lease cost	2,005	2,028	5,795	6,182
Cost of revenue
Lessee, Lease, Description [Line Items]
Operating lease cost	543	654	1,626	2,005
Cost of revenue | Operating Lease
Lessee, Lease, Description [Line Items]
Variable lease costs	100	200	300	400
Cost of revenue | Finance Lease
Lessee, Lease, Description [Line Items]
Variable lease costs	900	1,000	2,700	2,800
Selling, general and administrative expenses
Lessee, Lease, Description [Line Items]
Operating lease cost	635	622	1,892	1,957
Selling, general and administrative expenses | Operating Lease
Lessee, Lease, Description [Line Items]
Variable lease costs	$ 200	$ 200	$ 400	$ 400

v3.23.3

Leases - Future Minimum Lease Commitment (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Finance Lease Obligations
Remainder of 2023	$ 941
2024	3,139
2025	2,611
2026	2,109
2027	1,191
Thereafter	14,302
Total minimum lease payments	24,293
Financing Component	(11,993)
Net present value of minimum lease payments	12,300
Less: current portion of finance and operating lease obligations	(2,472)	$ (2,135)
Long-term finance and operating lease obligations	9,828	8,170
Operating Lease Obligations
Remainder of 2023	1,565
2024	3,988
2025	3,237
2026	3,120
2027	2,233
Thereafter	5,811
Total minimum lease payments	19,954
Financing Component	(3,152)
Net present value of minimum lease payments	16,802
Less: current portion of finance and operating lease obligations	(3,562)	(3,562)
Long-term finance and operating lease obligations	13,240	15,643
Sublease Receipts
Remainder of 2023	224
2024	912
2025	939
2026	967
2027	326
Thereafter	0
Total minimum lease payments	3,369
Non-Related Party
Operating Lease Obligations
Remainder of 2023	1,347
2024	3,322
2025	2,787
2026	2,670
2027	1,693
Thereafter	1,536
Total minimum lease payments	13,355
Financing Component	(1,676)
Net present value of minimum lease payments	11,679
Less: current portion of finance and operating lease obligations	(3,111)
Long-term finance and operating lease obligations	8,568
Related Party
Operating Lease Obligations
Remainder of 2023	218
2024	666
2025	450
2026	450
2027	540
Thereafter	4,275
Total minimum lease payments	6,599
Financing Component	(1,476)
Net present value of minimum lease payments	5,123
Less: current portion of finance and operating lease obligations	(451)
Long-term finance and operating lease obligations	4,672
Vehicles
Finance Lease Obligations
Remainder of 2023	813
2024	2,624
2025	2,083
2026	1,567
2027	636
Thereafter	0
Total minimum lease payments	7,723
Financing Component	(774)
Net present value of minimum lease payments	6,949	4,954
Less: current portion of finance and operating lease obligations	(2,472)
Long-term finance and operating lease obligations	4,477
Pontiac Facility
Finance Lease Obligations
Remainder of 2023	128
2024	515
2025	528
2026	542
2027	555
Thereafter	14,302
Total minimum lease payments	16,570
Financing Component	(11,219)
Net present value of minimum lease payments	5,351	$ 5,351
Less: current portion of finance and operating lease obligations	0
Long-term finance and operating lease obligations	$ 5,351

v3.23.3

Leases - Summary of Lease Terms and Discount Rates (Details)	Sep. 29, 2022	Sep. 30, 2023	Dec. 31, 2022
Weighted average lease term (in years):
Operating		6 years 6 months	6 years 11 months 23 days
Finance		3 years 1 month 13 days	2 years 8 months 23 days
Weighted average discount rate:
Operating		4.91%	4.76%
Finance		6.66%	5.06%
Lease agreement, term	25 years
Discount rate	11.11%

v3.23.3

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Operating cash flows from operating leases	$ 3,478	$ 3,890
Operating cash flows from finance leases	227	200
Financing cash flows from finance leases	2,032	2,051
Operating leases	1,043	0
Finance leases	4,062	2,171
Right-of-use assets disposed or adjusted modifying operating leases liabilities	643	(2,396)
Right-of-use assets disposed or adjusted modifying finance leases liabilities	$ 77	$ 77

v3.23.3

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands		4 Months Ended	9 Months Ended
	Jan. 23, 2020	Apr. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Loss estimated contingency				$ 2,200
Payment to acquire workers' compensation and general liability insurance			$ 250
Malpractice insurance, annual coverage limit			4,400
Surety Bond
Loss Contingencies [Line Items]
Debt outstanding			$ 99,700
Bernards Bros vs. Limbach Holdings, Inc.
Loss Contingencies [Line Items]
Issued an amended statement of decision awarding		$ 2,200
Bernards Bros vs. Limbach Holdings, Inc. | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, damages sought, value	$ 3,000

v3.23.3

Commitments and Contingencies - Schedule of Components of Self-Insurance (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Current liability — workers’ compensation and general liability	$ 99	$ 158
Current liability — medical and dental	422	557
Non-current liability	746	343
Total liability	1,267	1,058
Restricted cash	$ 65	$ 113

v3.23.3

Management Incentive Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation	$ 1,100	$ 800	$ 3,374	$ 1,980
2021 Amended And Restated Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance (in shares)	3,050,000		3,050,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, vesting period			3 years
Recognized stock-based compensation	$ 500	500	$ 1,200	1,200
RSUs | Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, vesting period			1 year
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, vesting period			3 years
Recognized stock-based compensation	700	$ 300	$ 2,200	700
PRSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares to be issued under grant			0.00%
PRSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares to be issued under grant			150.00%
Market-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance target, price per share (in dollars per share)			$ 18.00
Number of consecutive trading days within performance period to meet target share price			80 days
Performance period			3 years
MRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based costs	200		$ 200
Weighted average period to recognize share-based costs			1 year 3 months 3 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based costs	$ 3,900		$ 3,900
Weighted average period to recognize share-based costs			1 year 8 months 4 days
Fair value of awards vested			$ 3,800	$ 1,100

v3.23.3

Management Incentive Plans - RSUs Activity (Details) - RSUs	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Awards
Unvested at beginning of period (in shares) | shares	280,275
Granted (in shares) | shares	164,413
Vested (in shares) | shares	(163,354)
Forfeited (in shares) | shares	(42,131)
Unvested at end of period (in shares) | shares	239,203
Weighted-Average Grant Date Fair Value
Unvested at December 31, 2022 (usd per share) | $ / shares	$ 9.06
Granted (usd per share) | $ / shares	11.94
Vested (usd per share) | $ / shares	8.58
Forfeited (usd per share) | $ / shares	10.63
Unvested at March 31, 2023 (usd per share) | $ / shares	$ 11.09

v3.23.3

Management Incentive Plans - PRSUs Activity (Details) - PRSUs - $ / shares	3 Months Ended	9 Months Ended
	Mar. 31, 2023	Sep. 30, 2023
Awards
Unvested at beginning of period (in shares)	497,940	497,940
Granted (in shares)		289,092
Performance factor adjustment (in shares)	32,327	32,327
Vested (in shares)		(121,827)
Forfeited (in shares)		(116,911)
Unvested at end of period (in shares)		580,621
Weighted-Average Grant Date Fair Value
Unvested at December 31, 2022 (usd per share)	$ 8.32	$ 8.32
Granted (usd per share)		12.77
Performance factor adjustment (usd per share)		4.29
Vested (usd per share)		4.29
Forfeited (usd per share)		9.81
Unvested at March 31, 2023 (usd per share)		$ 10.85
Performance factor (percent)	136.13%
Pre-defined metric target, (percent)	100.00%

v3.23.3

Subsequent Events (Details) - ACME Industrial piping LLC - USD ($) $ in Thousands	Nov. 01, 2023	Jul. 03, 2023
Subsequent Event [Line Items]
Closing purchase price		$ 5,181
Subsequent Event
Subsequent Event [Line Items]
Closing purchase price	$ 13,500
Earnout payments	$ 6,500
Earnout Period	2 years

v3.23.3

Label	Element	Value
General Contractor (Construction Manager) Relationships Segment [Member]
Goodwill	us-gaap_Goodwill	$ 0
Owner Direct Relationships Segment [Member]
Goodwill	us-gaap_Goodwill	$ 11,370,000

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