My deck is only 12’x16’ with four steps on the one side. The brand of my composite is Fiberon and believe it or not, I installed it back in 2000! Hard to believe it’s 22 years old already….doesn’t look it! Your product is by far the best for my deck as others just don’t cut it. I only used a pressure washer this spring and it just doesn’t remove the spots. I’m starting to get the black mold and always had the best results with your product. Been buying it for years at Lowes however it’s not available on its website anymore. I will spread the word about how good your product is. Need to make it easier to get by selling it at big box retailers!!!!