TREX CO INC — Director's Dealing 2013

Oct 29, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TREX CO INC (TREX)
CIK: 0001069878
Period of Report: 2013-10-25

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

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-10-25	Common Stock	M	1500	$24.17	Acquired	37725	Direct
2013-10-25	Common Stock	M	11920	$17.41	Acquired	49645	Direct
2013-10-25	Common Stock	D	3632	$67.12	Disposed	46013	Direct
2013-10-25	Common Stock	F	4619	$67.12	Disposed	41394	Direct
2013-10-25	Common Stock	S	4272	$59.00	Disposed	37122	Direct
2013-10-28	Common Stock	M	4475	$38.51	Acquired	41597	Direct
2013-10-28	Common Stock	S	4475	$68.4774	Disposed	37122	Direct
2013-10-28	Common Stock	S	5169	$67.9674	Disposed	31953	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-10-25	Stock Appreciation Right	$24.17	M	1500	Disposed	2016-02-08	Common Stock (1500)	Direct
2013-10-25	Stock Appreciation Right	$17.41	M	11920	Disposed	2020-02-17	Common Stock (11920)	Direct
2013-10-28	Stock Options (Right to Buy)	$38.51	M	4475	Disposed	2014-02-19	Common Stock (4475)	Direct

Footnotes

F1: 1,500 Stock Appreciation Rights (SARs) are being exercised pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 7, 2013.

F2: 11,920 Stock Appreciation Rights (SARs) are being exercised pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 7, 2013.

F3: 4,619 shares are being surrendered as allowed by the Company's 2005 Stock Incentive Plan to cover the payment of taxes currently due on the exercise of stock appreciation rights.

F4: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 7, 2013.

F5: Options exercised prior to expiration date of 2/19/2014, and resulting shares sold, pursuant to Rule 10b5-1 trading plan adopted by the reporting person on August 7, 2013.

F6: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $66.69 to $69.89, inclusive. The reporting person undertakes to provide Trex Company, Inc., any security holder of Trex Company, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in Footnote (6) to this Form 4.

F7: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $67.75 to $68.12, inclusive. The reporting person undertakes to provide Trex Company Inc., any security holder of Trex Company, Inc. , or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in Footnote (7) to this Form 4.

F8: This stock appreciation right becomes exerciseable in approximately three equal annual installments beginning on the first anniversary of the February 8, 2006 grant date.

F9: The stock appreciation right becomes exercisable in three equal installments beginning on the first anniversary of the grant date.