Do some of the other lye or sodium hydroxide-based roof cleaners work well?
Unfortunately, they do not. The shingle manufacturers do not recommend these roof cleaning products because they are not very effective. They only work when used in conjunction with excessive pressure from a pressure washer, which leads to lessened longevity of the roof. When not used with pressure, some of these products even state on the label that the roof may take 2-3 months to begin appearing clean after an application, and in some cases more than one roof cleaning application is necessary.
