Exhibit 99.1

Trex Company Announces First-Quarter 2012 Sales of $96.1 Million

and EPS of $0.74

New Product Introductions and Manufacturing Improvements Contribute to Strong Performance

WINCHESTER, Va. – May 7, 2012 – Trex Company, Inc. (NYSE: TREX), the world’s largest manufacturer of wood-alternative decking and railing products, today announced financial results for the first quarter ended March 31, 2012.

Net sales for the first quarter of 2012 totaled $96.1 million compared to net sales of $69.0 million for the 2011 first quarter, an increase of 39%. As described in the 2011 fourth quarter press release, the Company did not increase prices in 2012. This led to a more normal product demand in the 2012 quarter. The Company reported net income of $12.3 million, or $0.74 per diluted share, for the 2012 period compared to net income of $5.1 million, or $0.30 per diluted share, for the prior-year period. The Company’s 2011 results reflected a favorable resolution of uncertain tax positions that positively impacted income taxes by $2.6 million. Excluding that adjustment, net income in the 2011 first quarter was $2.5 million, or $0.15 per diluted share.

Chairman, President and CEO Ronald W. Kaplan commented, “Our first quarter sales were 7% above guidance. Our best-in-class product platform, combined with market share gains, helped us exceed our revenue target. Today’s results also represent the second highest first-quarter EPS performance since the Company went public in 1999.

“Demand for our 2011 new product introductions, particularly Trex Enhance™ and Trex Transcend^® Porch, contributed significantly to our strong showing. Our expansion into the international arena also gained momentum, with a substantial year-over-year sales increase. Our manufacturing and productivity initiatives continued to deliver important benefits, contributing to our gross margin of 36.9%, up 350 basis points from the 2011 period.”

Mr. Kaplan concluded, “We continue to see a strong shift in the market towards ultra-low-maintenance wood alternative products. With our expanding ultra-low-maintenance product offering, utilizing Transcend technology, we are off to a great start for the year. Based on the market demand we are currently seeing, we expect net sales of approximately $90 million for the second quarter of 2012, an increase of 15% from last year’s period.”

First-Quarter 2012 Conference Call and Webcast Information

Trex will hold a conference call to discuss its first-quarter 2012 results on Monday, May 7, 2012 at 10:00 a.m. ET. To participate in the live call by telephone, please dial 706-634-1218 or 888-803-7566 and reference conference ID #70002443. A live webcast of the conference call will also be available in the Investor Relations section of the Trex Company website at trex.com.

For those who cannot listen to the live broadcast, the webcast will be available on Trex’s website for 30 days. A telephone replay of the call will also be available for seven days, beginning at approximately 1:00 p.m. ET on Monday, May 7, 2012. To listen to the telephone replay, dial 404-537-3406 and enter conference ID #70002443.

Forward-Looking Statements

The statements in this press release regarding the Company’s expected future performance and condition constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These statements are subject to risks and uncertainties that could cause the Company’s actual operating results to differ materially. Such risks and uncertainties include the extent of market acceptance of the Company’s products; the costs associated with the development and launch of new products and the market acceptance of such new products; the sensitivity of the Company’s business to general economic conditions; the Company’s ability to obtain raw materials at acceptable prices; the Company’s ability to maintain product quality and product performance at an acceptable cost; the level of expenses associated with product replacement and consumer relations expenses related to product quality; and the highly competitive markets in which the Company operates. Documents filed with the Securities and Exchange Commission by the Company, including in particular its latest annual report on Form 10-K and quarterly reports on Form 10-Q, discuss some of the important factors that could cause the Company’s actual results to differ materially from those expressed or implied in these forward-looking statements. The Company expressly disclaims any obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise.

About Trex Company

Trex Company is the world’s largest manufacturer of wood-alternative decking and railing, with more than 20 years of product experience. Stocked in more than 5,500 retail locations throughout the world, Trex^® outdoor living products offer a wide range of style options with fewer ongoing maintenance requirements than wood, as well as a truly environmentally responsible choice. For more information, visit trex.com.

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TREX COMPANY, INC.

Condensed Consolidated Statements of Comprehensive Income

(In thousands, except share and per share data)

(Unaudited)

TREX COMPANY, INC.

Condensed Consolidated Balance Sheets

(In thousands, except share data)

(unaudited)

TREX COMPANY, INC.

Condensed Consolidated Statements of Cash Flows

(In thousands)

(Unaudited)