We live outside of Boston and we have used Corte clean on our deck since it was new. Corte clean really works we follow the directions and the before and after pictures are night and day. Over the years when you use a new product it almost never does what the manufacturer claims but in this case Corte clean is worth every Penney you spend. One year I called to order and the person on the phone suggested sprinkling some Corte clean powder before the first snow storm if I had any leftover so we did and it worked awesome. Between watching a YouTube video on how to use it or just getting advise when you call them Corte Clean works there people are great to deal with if you have any questions. When you grow up in the northeast we tend to be very skeptical so for us to rave about a great product that really means something.