Exhibit A

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1) of the Securities Exchange Act of 1934, as amended, each of the undersigned hereby agrees to the joint filing of the Schedule 13D to which this agreement is attached and to the joint filing of all amendments thereto. Notwithstanding the foregoing, each of the JLL Reporting Persons and the Warburg Pincus Reporting Persons disclaims beneficial ownership of shares of the Company’s Common Stock beneficially owned by the other Reporting Persons.

This agreement may be executed in one or more counterparts, each of which shall be considered an original counterpart, and shall become a binding agreement when each of the parties designated as signatories has executed one counterpart.

Dated: June 24, 2010

BUILDING PRODUCTS, LLC

/s/ Paul S. Levy

Paul S. Levy, Manager

JLL BUILDING HOLDINGS, LLC

By JLL Partners Fund V, L.P.

By its General Partner, JLL Associates V, L.P.

By its General Partner, JLL Associates G.P. V, L.L.C.

/s/ Paul S. Levy

Paul S. Levy, as Managing Member of JLL Associates G.P. V, L.L.C.

JLL PARTNERS FUND V, L.P.

By its General Partner, JLL Associates V, L.P.

By its General Partner, JLL Associates G.P. V, L.L.C.

/s/ Paul S. Levy

Paul S. Levy, as Managing Member of JLL Associates G.P. V, L.L.C.

JLL ASSOCIATES V, L.P.

By its General Partner, JLL Associates G.P. V, L.L.C.

/s/ Paul S. Levy

Paul S. Levy, as Managing Member of JLL Associates G.P. V, L.L.C.

JLL ASSOCIATES G.P. V, L.L.C.

/s/ Paul S. Levy

Paul S. Levy, as Managing Member

/s/ Paul S. Levy

Paul S. Levy

WARBURG PINCUS PRIVATE EQUITY IX, L.P.

By its General Partner, Warburg Pincus IX, LLC

By its Sole Member, Warburg Pincus Partners, LLC

By its Managing Member, Warburg Pincus & Co.

/s/ Scott A. Arenare

Scott A. Arenare

Partner

WARBURG PINCUS IX, LLC

By its Sole Member, Warburg Pincus Partners, LLC

By its Managing Member, Warburg Pincus & Co.

/s/ Scott A. Arenare

Scott A. Arenare

Partner

WARBURG PINCUS PARTNERS, LLC

By its Managing Member, Warburg Pincus & Co.

/s/ Scott A. Arenare

Scott A. Arenare

Partner

WARBURG PINCUS LLC

/s/ Scott A. Arenare

Scott A. Arenare

Managing Director

WARBURG PINCUS & CO.

/s/ Scott A. Arenare

Scott A. Arenare

Partner

/s/ Scott A. Arenare

Charles R. Kaye

By:   Scott A. Arenare

        Attorney-in-Fact

/s/ Scott A. Arenare

Joseph P. Landy

By:   Scott A. Arenare

        Attorney-in-Fact

JWP LLC

By JLL Building Holdings, LLC

By its sole Member, JLL Partners Fund V, L.P.

By its General Partner, JLL Associates V, L.P.

By its General Partner, JLL Associates G.P. V, L.L.C.

/s/ Paul S. Levy

Paul S. Levy, as Managing Member of JLL Associates G.P. V, L.L.C.

By Warburg Pincus Private Equity IX, L.P.

By its General Partner, Warburg Pincus IX, LLC

By its Sole Member, Warburg Pincus Partners, LLC

By its Managing Member, Warburg Pincus & Co.

/s/ Scott A. Arenare

Scott A. Arenare

Partner