X0306 4 2023-03-01 0001069878 TREX CO INC TREX 0001512909 Zambanini Adam Dante 160 EXETER DRIVE WINCHESTER VA 22603 1 President, Trex Residential Pr Common Stock 2023-03-01 4 F 0 531 50.40 D 182338 D Common Stock 2023-03-01 4 J 0 1681 50.40 D 180657 D 531 shares are being surrendered as allowed by the Company's 2014 Stock Incentive Plan to cover payment of taxes currently due on previously granted restricted stock units. Represents the target number of performance-based restricted units which did not vest due to the performance condition not being satisfied. /s/ Amy M. Fernandez by power of attorney 2023-03-03