LOUISVILLE PRESSURE WASHING specializes in removing those unsightly Black Streaks from Roofs. The streaks are caused by a spore of algae that feeds on the limestone in shingles. Shingle manufacturers put limestone in shingles to add weight, keeping them from blowing right off your roof. Allowing the algae to feed on the limestone will decrease the life of your shingles. Letting a contractor Pressure Wash your shingles will also remove the limestone, decreasing the life of your roof. Pressure Pros – Louisville Pressure Washing simply applies their safe and effective detergent, Pressure Pros Streak Away, that kills the algae and removes the streaks within hours. Our ROOF CLEANING is Guaranteed or you don’t PAY.