X0202 4 2005-06-20 0001069878 TREX CO INC TWP 0001105733 MATHENY ROBERT G 160 EXETER DRIVE WINCHESTER VA 22603-8605 1 1 0 0 Chairman and CEO Common Stock 2005-06-20 2005-06-20 4 S 0 5000 38.3 D 1085089 D Does not include Indirect Beneficial Ownership of 1000 shares by wife. Mr. Matheny disclaims beneficial ownership of these securities, and this report shall not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or any other purpose. Lynn E. MacDonald 2005-06-21