I have to say its only been a year since this finish went on. Some of you know that the original system failed after about seven years, even with recommended maintainence. It was stripped and restained with the Sikkens. I love how it looks! It repels water like a well waxed car. I like to go green whenever possible, however, not this time. I can't keep up with a house this size in my environment. So, I guess we wait.