Black stains on a roof are not dirt. It’s actually a bacteria called Gleocapsa Magma or roof algae. The rain pulls colonies down the roof causing it to streak. The algae feeds on the limestone that is in all shingle roofs. An abundant food source coupled with the humidity in the south makes your roof a perfect breeding ground. After time the algae will give way to even more damaging organisms like moss and lichens.
Contact us for a free estimate. See just how reasonable it can be to improve and maintain the quality of your home. ProClean Power & Soft Wash serves Maryville, Knoxville, and surrounding areas.
ProClean’s roof cleaning method safely evens out the original tone of shingle roofing without the use of high pressure. We protect all surrounding vegetation.
We also specialize in clay, tile, metal, and slate roofs.
How to clean shingles
http://www.asphaltroofing.org/ recommends A 50/50 mix of household chlorine bleach and water. This can be applied with a pump up sprayer. For the diy home owner, this can be an extremely dangerous task. Be sure to tie off properly and wear the correct PPE. ProClean Power & Soft Wash takes it a few steps further with our soft wash roof cleaning solution. Bleach and water is not enough to thoroughly and effectively kill roof algae. We use a commercial grade detergent that is specifically formulated to hold the bleach to roofs and other steep surfaces, allowing adequate dwell time. We also use only industrial grade bleach not found at any store. It’s at higher concentration and always fresh. The other additives in store bleach can harm paint and other surfaces around the house. Never pressure wash shingles. Blasting at them will not kill the algae and blows off the granules. ProClean uses a 100 psi roof pump and can treat most roofs from the gutter line. The detergents are left and will safely rinse off with the first rain, taking dead moss and lichen with it. The black algae streaks will disappear just minutes after being treated. Be sure to protect vegetation on the ground by either covering or rinsing before, during and after the treatment.
The products provided at big box home improvement stores are not very effective. It can take up to 3 treatments to see desired results.