How long will it take for roof stains to disappear using the “no rinse” application method?
The stains will disappear in 6-9 months, on average, using 9 gallons water to one gallon of Spray & Forget mixture. A stronger concentration can be used to expedite the process. For example, a 5:1 mix will remove the stains in about 3-6 months on average. The removal time is also dependent on rainfall and the severity of the infestation.