Guys, need to back up here. The picture shows an older generation of Trex. The link provided for cleaning of Trex is for the newer "Transcends" and NOT for the older generation of Trex. If you follow that cleaning method you will be in some serious trouble. The old Trex will be severely damaged by 3000psi. Also, to clean the Trex properly without using the recommended Corte Clean you can use your house wash solution and add chlorine bleach to it. Make it a little stronger than you do for the house and rely on dwell time. You will need about 10 minutes and then scrub with a deck brush. When finished rinse with the pressure washer if you like but stay over 12 inches away and less than 1000psi just use to rinse surfaces. When we do it we use ONLY a garden hose. After rinsing it is important to apply an oxalic acid based brightener to the surfaces while wet. This will neutralize the tannins that are in the composite. The wood content in Trex is oak and leaves black spots as well. If you do this it will appear 90% or better when finished and dry. If when you are finished and you still see some black spots don't worry, next day and when it is dry you will be fine. Most people are under the wrong impression and think the black spots on composites are all mold and mildew. FALSE, there are also black spots from the wood content used in the composites and Trex is not the only one. Cleaning as instructed above will address the issues and leave the customer very happy and you paid.
