The black streaking on Florida roofs is an algae called Gloeocapsa magma. It feeds on the limestone filler in asphalt shingles and holds heat against the roof. It gets treated, never pressure washed: high pressure strips the granules that are the roof's actual weather protection and takes years off its life. We apply a low-pressure soft wash solution that kills the organism, then the rain carries it off over the following weeks. Roof soft washing starts at $399. If your roof is streaked but the shingles are otherwise sound, this is the cheapest thing you can do to make a house look ten years newer.
