USG Corporation

Chicago, Illinois, USA, 21 March 2007 -- USG Corporation (NYSE: USG) announced today the closing of its previously announced underwritten public offering of 8,230,500 shares of its common stock at a price of USD 48.60 per share.

The offering was made pursuant to an effective shelf registration statement that USG filed with the Securities and Exchange Commission on 12 March 2007. The net proceeds of the offering after deducting underwriting discounts and commissions and offering expenses were approximately USD 383 million. In connection with the offering, USG has granted the underwriters a 30-day option to purchase up to an additional 1,234,575 shares of its common stock.

USG intends to use a portion of the net proceeds to pay the purchase price at consummation of the previously announced acquisition by USG's subsidiary, L&W Supply Corporation, of California Wholesale Material Supply, Inc. and specified affiliates, should it occur. USG intends to use the remaining net proceeds of the offering for general corporate purposes.

Goldman, Sachs & Co. and JPMorgan acted as joint book-running managers in the offering.

Any offering of shares of common stock shall be made only by means of a prospectus. Copies of the prospectus supplement and accompanying prospectus relating to the offering can be obtained from Goldman, Sachs & Co., Attn: Prospectus Department, 85 Broad Street, New York, New York 10004, via fax at 212-902-9316 or via email at prospectus-ny@ny.email.gs.com or JPMorgan, National Statement Processing, Prospectus Library, 4 Chase Metrotech Center , CS Level, Brooklyn, New York 11245 or via phone at 718-242-8002.

USG Corporation is a Fortune 500 manufacturer and distributor of high-performance building systems through its United States Gypsum Company, USG Interiors, Inc., and L&W Supply Corporation subsidiaries. Headquartered in Chicago, USG serves the residential and nonresidential construction markets, repair and remodel construction markets, and industrial processes. USG's wall, ceiling, flooring, and roofing products provide leading-edge building solutions for customers, while L&W Supply center locations efficiently stock and deliver building materials nationwide.