I have been using this product for6/7 years I live in the woods and things get dirty.The year after we got the tree deck I thought I had made a terrible mistake,the deck was so dirty. The people I spoke with recommended Corti Clean. It worked like a miracle ,deck was as clean as brand new.Spray it on ,let it sit ,clean with hose. I'm older and it was easy for me .Strangers still ask if my deck is new.