Use isopropyl alcohol to remove the product identification markings. Soak a rag with the alcohol and rub away the markings. Rinse clean with water.
Use a composite deck cleaner. TimberTech recommends using an eco-friendly product such as Corte-Clean. Follow manufacturer directions. Usually, you need to clean off your deck or fence with a hose and then evenly apply diluted cleaning solution. Then use a brush to scrub the TimberTech clean. Rinse when finished and allow it to dry.
Power wash your TimberTech. Using the same kind of deck cleaning solution in step two, TimberTech states it is safe to power wash with a maximum pressure of 1500 psi for their decks and 1200 psi for their fences and railings. Use a flat-tip nozzle and spray in the direction of the grain. Follow the power washer manufacturer's directions and all safety precautions.