My husband and I installed a TimberTech composite deck to replace the old rotted out wood deck on our condo in Ohio. We didn't want to have to sand, paint and seal anymore. We were looking for less maintenance. To our surprise, mold showed up, so we bought a pressure washer to clean it. Using it was a lot of effort and didn't get the deck clean! Additionally, we were worried about permanently damaging the expensive decking, as so many of our neighbors have done. Most are now black with mold. Their decks look awful and they cover them with rugs. I called TimberTech and they recommended Corte Clean. I am very happy with the product. We have now been using it for 3 or 4 years. It works so well, I sold the power washer because I no longer need it. I am very happy with the product and the way it cleans.