What are those Black Streaks on your Roof?
A. Oliveri Soft Wash Roof Cleaning 631-588-5032 www.SoftWashLI.com Servicing Suffolk County NY Roof Algae: Black Streaks your Shingles Black streaks running down your roof aren't a sign that the asphalt shingles are dissolving or that you need a new roof. Rather, you have roof algae. The organisms arrive on the rooftop as either spores or clumps of cells. If they land on the north side of the roof, where the sun is less harsh and moisture more plentiful, the algae will have a good environment to multiply, spreading in a delta down the slope of the roof. Asphalt shingles contain limestone, which makes them heavy, durable and reflective. Roof algae over time will slowly consume the limestone, ultimately weakening the shingles. Algae cells produce a dark pigment that...