TREX CO INC — Director's Dealing 2011

May 16, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TREX CO INC (TREX)
CIK: 0001069878
Period of Report: 2011-05-13

Reporting Person: ROBINSON PATRICIA B (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-05-13	Common Stock	M	372	$19.25	Acquired	372	Direct
2011-05-13	Common Stock	S	172	$29.84	Disposed	200	Direct
2011-05-13	Common Stock	S	100	$29.88	Disposed	100	Direct
2011-05-13	Common Stock	S	100	$29.89	Disposed	0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-05-13	Stock Options (Right to Buy)	$19.25	M	372	Disposed	2011-07-02	Common Stock (372)	Direct