TREX CO INC — Director's Dealing 2012

Sep 5, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TREX CO INC (TREX)
CIK: 0001069878
Period of Report: 2012-09-04

Reporting Person: Gupp William R. (CAO, Gen. Counsel & Secretary)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-09-04	Common Stock	M	1418	$9.14	Acquired	50595	Direct
2012-09-04	Common Stock	D	422	$30.71	Disposed	50173	Direct
2012-09-04	Common Stock	F	421	$30.71	Disposed	49752	Direct
2012-09-04	Common Stock	S	200	$30.84	Disposed	49552	Direct
2012-09-04	Common Stock	S	200	$30.81	Disposed	49352	Direct
2012-09-04	Common Stock	S	300	$30.80	Disposed	49052	Direct
2012-09-04	Common Stock	S	50	$30.79	Disposed	49002	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-09-04	Stock Appreciation Right	$9.14	M	1418	Disposed	2018-05-07	Common Stock (1418)	Direct

Footnotes

F1: 1,418 Stock Appreciation Rights (SARs) are being exercised pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 14, 2011

F2: 421 shares are being surrendered as allowed by the Company's 2005 Stock Incentive Plan to cover payment of taxes currently due on the exercise of SARs.

F3: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 14, 2011.

F4: The stock appreciation right becomes exerciseable in three equal installments beginning on the first anniversary date of the transaction date.