UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

June 14, 2013

(Date of earliest event reported)

QUANEX BUILDING PRODUCTS CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: 713-961-4600

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Item 1.01. Entry into a Material Definitive Agreement

The disclosure set forth below under Item 5.02 relating to the Company’s agreements with Martin Ketelaar and Dewayne Williams are incorporated into this Item 1.01.

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Departure of Named Executive Officer

Effective June 14, 2013, Jairaj T. Chetnani departed from his employment with Quanex Building Products Corporation (the “Company”). Effective the same day, Martin Ketelaar assumed the position of Vice President –Treasurer & Investor Relations of the Company.

On June 20, 2013, Quanex Building Products Corporation (the “Company”) announced that its Board of Directors has elected Dewayne Williams, 42, to serve as Vice President – Controller of the Company, effective July 1, 2013.

Prior to joining the Company, Mr. Williams was most recently the Chief Accounting Officer, Vice President – Corporate Controller and Assistant Treasurer to Complete Production from 2005 until it was acquired by Superior Energy Services in 2012. Since that time, he was engaged in consulting work to facilitate the transaction for Superior Energy.

Agreements with Mr. Williams

In connection with Mr. Williams’ appointment, the Company and Mr. Williams entered into an agreement (the “Williams Agreement”), a change in control agreement (the “Williams Change in Control Agreement”) and an indemnity agreement (the “Williams Indemnity Agreement”), each effective as of July 1, 2013.

The following discussion is qualified by reference to the Williams Agreement, a copy of which is attached hereto as Exhibit 10.1 and incorporated herein by reference; the Williams Change in Control Agreement, the form of which is attached hereto as Exhibit 10.2 and incorporated herein by reference; and the Williams Indemnity Agreement, the form of which was filed as Exhibit 10.2 of the Company’s Current Report on Form 8-K (Reg. No. 001-33913), as filed with the Securities and Exchange Commission on August 29, 2008, and incorporated herein by reference.

Under the Williams Agreement, the Company will provide the following:

Under the Williams Change in Control Agreement, the Company will provide the following benefits in the event that Mr. Williams’ employment is terminated following a Change in Control of the Company (as defined in the Wiliams Change in Control Agreement), if such termination is (x) by the Company for any reason other than occurrence of an Event of Termination for Cause, or (y) by Mr. Williams after the occurrence of an Event of Termination for Good Reason (as defined in the Williams Change in Control Agreement):

A brief summary of the terms of the Williams Indemnity Agreement can be found in the Company’s Current Report on Form 8-K (Reg. No. 001-33913), as filed with the Securities and Exchange Commission on August 29, 2008, and incorporated herein by reference.

Agreements with Mr. Ketelaar

In connection with Mr. Ketelaar’s appointment, the Company and Mr. Ketelaar entered into an agreement (the “Ketelaar Agreement”), a change in control agreement (the “Ketelaar Change in Control Agreement”) and an indemnity agreement (the “Ketelaar Indemnity Agreement”), each effective as of June 14, 2013.

The following discussion is qualified by reference to the Ketelaar Agreement, a copy of which is attached hereto as Exhibit 10.4 and incorporated herein by reference; the Ketelaar Change in Control Agreement, the form of which is attached hereto as Exhibit 10.5 and incorporated herein by reference; and the Ketelaar Indemnity Agreement, the form of which was filed as Exhibit 10.2 of the Company’s Current Report on Form 8-K (Reg. No. 001-33913), as filed with the Securities and Exchange Commission on August 29, 2008, and incorporated herein by reference.

Under the Ketelaar Agreement, the Company will provide the following:

Under the Ketelaar Change in Control Agreement, the Company will provide the following benefits in the event that Mr. Ketelaar’s employment is terminated following a Change in Control of the Company (as defined in the Ketelaar Change in Control Agreement), if such termination is (x) by the Company for any reason other than occurrence of an Event of Termination for Cause, or (y) by Mr. Ketelaar after the occurrence of an Event of Termination for Good Reason (as defined in the Ketelaar Change in Control Agreement):

A brief summary of the terms of the Ketelaar Indemnity Agreement can be found in the Company’s Current Report on Form 8-K (Reg. No. 001-33913), as filed with the Securities and Exchange Commission on August 29, 2008, and incorporated herein by reference.

Item 8.01 Other Events.

On June 20, 2013, the Company issued a press release (the “Press Release”) announcing the election of Mr. Williams as Vice President – Controller of the Company and of Mr. Ketelaar as Vice President – Investor Relations and Treasurer of the Company. The foregoing is qualified by reference to the Press Release which is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits.

Not applicable

Not applicable

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Exhibit Index