How To Clean Composite Decking Material. Do not use a natural fiber deck brush on capped composite decking material, as these can dull the surface. Once the deck has been scrubbed, rinse thoroughly with clean water, ensuring all the soapy water has been rinsed clear from the deck.
This is also a quick and easy step because all you have to do is just take out the hose and start spraying the composite. Make sure downspouts point elsewhere so the material doesn’t get excess exposure to moisture. Always scrub in the direction of the deck plank.
When shopping for a cleaner, make sure to look closely at the label and never choose a “deck cleaner” that is chlorine.
Mix warm water (not too hot) and a mild dish soap in a bucket, and use a soft bristled brush to gently scrub the dirt away. When cleaning composite decking, some homeowners make mistakes that can increase the amount of care they’ll have to perform on their deck later. For general cleaning, use a dilution of mild liquid soap and water. Do not use a wire brush as that will thoroughly scratch your plastic decking.