TREX CO INC — Director's Dealing 2019

May 2, 2019

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TREX CO INC (TREX)
CIK: 0001069878
Period of Report: 2019-04-30

Reporting Person: Cline James E (Director, President and CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2019-04-30	Common Stock	M	10256	$20.585	Acquired	81897	Direct
2019-04-30	Common Stock	D	3048	$69.27	Disposed	78849	Direct
2019-04-30	Common Stock	F	3251	$69.27	Disposed	75598	Direct
2019-04-30	Common Stock	M	11424	$10.97	Acquired	87022	Direct
2019-04-30	Common Stock	D	1810	$69.27	Disposed	85212	Direct
2019-04-30	Common Stock	F	4336	$69.27	Disposed	80876	Direct
2019-05-01	Common Stock	S	9235	$68.2247	Disposed	71641	Direct
2019-05-01	Common Stock	S	2745	$68.7428	Disposed	68896	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2019-04-30	Stock Appreciation Right	$20.585	M	10256	Disposed	2025-08-17	Common Stock (10256)	Direct
2019-04-30	Stock Appreciation Right	$20.585	M	11424	Disposed	2025-08-17	Common Stock (11424)	Direct

Footnotes

F1: Stock Appreciation Rights are being exercised pursuant to a Rule 10b5-1 sales plan adopted by the reporting person on August 1, 2018.

F2: Shares are being surrendered as allowed by the Company's 2014 Stock Incentive Plan to cover payment of taxes currently due on previously granted SARs.

F3: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 sales plan adopted by the reporting person on August 1, 2018.

F4: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $68.1509 to $68.8804, inclusive.

F5: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $68.50 to $69.09, inclusive.