NCS Nci Building Systems New

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Explanatory Note

This Amendment No. 12 to Schedule 13D (this “Amendment No. 12”) amends and supplements the Schedule 13D originally filed with the United States Securities and Exchange Commission (the “SEC”) on October 30, 2009 (the “Initial Statement”), as amended prior to the date hereof (as so amended, the “Statement”). This Amendment No. 12 is being filed on behalf of the reporting persons (the “Reporting Persons”) identified on the cover pages of this Amendment No. 12.

Item 1. Security and Issuer

Item 1 is hereby amended as follows:

This Amendment No. 12 is being filed with respect to shares of Common Stock held by the Reporting Persons. Such shares were issued to the Reporting Persons upon conversion of the shares of Series B Cumulative Convertible Participating Preferred Stock, as further disclosed in Amendment No. 9 to the Statement, as filed with the SEC on May 14, 2013.

Item 2. Identity and Background

The agreement among the Reporting Persons relating to the joint filing of this Amendment No. 12 is attached as Exhibit 1 hereto.

Item 4. Purposes of the Transaction.

Item 4 is hereby amended and supplemented by adding the following :

Pursuant to an Underwriting Agreement, dated December 11, 2017 (the “Underwriting Agreement”), among Clayton, Dubilier & Rice Fund VIII, L.P. (“Fund VIII”), CD&R Friends & Family Fund VIII, L.P. (“F&F Fund VIII”, and together with Fund VIII, the “CD&R Funds”), and Goldman Sachs & Co. LLC (“Goldman”) and RBC Capital Markets, LLC (“RBC” and, together with Goldman, the “Underwriters”), on December 13, 2017 Fund VIII sold 7,132,145 and F&F Fund VIII sold 17,855 shares of the Company’s Common Stock, in each case to the Underwriters at a price of $19.36 per Share, in a registered offering (the “Secondary Offering”). Pursuant to the Underwriting Agreement, at the CD&R Funds request, the Company purchased 1,150,000 shares of the Common Stock from the Underwriters in the Secondary Offering at a price per share equal to the price at which the Underwriters purchased the shares from the CD&R Funds.

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Pursuant to the Underwriting Agreement, the CD&R Funds have agreed with the Underwriters not to offer or sell, dispose of or hedge, directly or indirectly, any common stock of the Company without the permission of the Underwriters for a period of 45 days from December 11, 2017, subject to certain exceptions.

The foregoing description of the Underwriting Agreement does not purport to be complete and is qualified in its entirety by reference to the Underwriting Agreement, which is filed as Exhibit 15 hereto and is incorporated herein by reference.

Except as described in this Item 4 and Item 6 of this Statement which are incorporated herein by reference, the Reporting Persons have no present plans or proposals that relate to or would result in any of the actions required to be reported herein.

Item 5. Interest in the Securities of the Issuer.

Item 5 is hereby amended and restated in its entirety as follows:

As of the date hereof, each of the Reporting Persons beneficially owns the number and percentage of Shares of the Company then issued and outstanding listed opposite its name:

Amounts set forth in this Amendment No. 12 do not include certain shares of Common Stock issued to Clayton, Dubilier & Rice, LLC (“CD&R, LLC”), as assignee of director compensation payable to certain members of the Issuer’s board of directors who are affiliated with the CD&R Funds.

CD&R Investment Associates VIII, Ltd. is managed by a two-person board of directors. Donald J. Gogel and Kevin J. Conway, who, as the directors of CD&R Investment Associates VIII, Ltd., may be deemed to share beneficial ownership of the shares of the Issuer’s Common Stock in which the CD&R Funds have beneficial ownership. Such persons expressly disclaim such beneficial ownership. Investment and voting decisions with respect to the shares of the Issuer’s Common Stock held by the CD&R Funds are made by an investment committee of limited partners of CD&R Associates VIII, L.P., currently consisting of more than ten individuals (the “Investment Committee”). The investment professionals who have effective voting

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control of the Investment Committee are Michael G. Babiarz, Manvinder Singh Banga, James G. Berges, John C. Compton, Kevin J. Conway, Russell P. Fradin, Thomas C. Franco, Kenneth A. Giuriceo, Donald J. Gogel, Jillian Griffiths, Marco Herbst, Sarah Kim, John Krenicki, Jr., David A. Novak, Paul S. Pressler, Christian Rochat, Ravi Sachdev, Richard J. Schnall, Steven Shapiro, Nathan K. Sleeper, Derek L. Strum, Sonja Terraneo, David H. Wasserman and Jonathan L. Zrebiac. All members of the Investment Committee expressly disclaim beneficial ownership of the shares of the Issuer’s Common Stock shown as beneficially owned by the CD&R Funds.

Each of CD&R Associates VIII, L.P., CD&R Associates VIII, Ltd. and CD&R Investment Associates VIII, Ltd. expressly disclaims beneficial ownership of the shares held by the CD&R Funds and by CD&R, LLC and of stock options held by CD&R, LLC as assignee of director compensation payable to certain of the Issuer’s directors. The CD&R Funds expressly disclaim beneficial ownership of the shares of Common Stock held by CD&R, LLC. CD&R, LLC expressly disclaims beneficial ownership of the shares of Common Stock held by the CD&R Funds.

(c) The information set forth in Item 4 is incorporated by reference herein in response to this Item 5(c).

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

Item 6 of the Statement is hereby amended by inserting the following information:

The information set forth in Item 4 above is hereby incorporated by reference in response to Item 6.

Item 7. Material to be filed as exhibits.

Item 7 is hereby amended and supplemented by adding the following:

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: December 14, 2017

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