ROOF WASH

Like every other part of your home, it requires routine maintenance. … Cleaning will increase the life expectancy of your roof. Debris, stains, moss, and lichen do more than detract from the appearance and value of your home. They can create more serious issues later. If you allow large patches of moss to grow on your roof, these patches hold water against the surface of the roof, which can cause the roofing materials to rot.

The black streaks running down roofs are actually hardy algae called Gloeocapsa magma. As the blue-green algae accumulate, they develop a dark, hardened outer coating, which results in the black stains you see. The algae feed on the limestone in shingles. Roof algae are not harmful or dangerous in itself, but after a period of time, the algae can cause the protective UV granules that cover roofing shingles to begin to come off, eventually drying them out. In other words, you are going to need to replace your roofing shingles sooner than expected.