How Did My Roof Get Algae

Roof algae prevention tips.

How did my roof get algae.

Although algae can be found on all types of roofing it tends to be most common on asphalt shingles. Thousands of roof on homes and other buildings suffer from black streaks. A copper strip at the top of the roof can prevent future roof algae. This is what makes those unattractive black streaks on your roof.

Common algae that form on roof surfaces including asphalt shingles and roll roofing include the algae shown above and gleocapsa magma a species that generally appears black on the roof surface but under some lighting conditions even on the roof gleocapsa magma can appear as a blue green color as might other algae genera species. The most common class of roof algae is gloeocapsa magma a bacterium that eats water and expels oxygen. Roof algae generally have a black green hue. Algae spores are airborne.

To remove roof algae a solution of oxygen bleach can be applied to the roof shingles and then rinsed off. Algae grow most often on wood and asphalt shingles or concrete tiles especially if they do not get a lot of sunlight. All of these options have been tested and show clear signs of decreasing and eventually preventing algae growth. You may think you have roof algae when really you have moss mildew or mold.

When it comes to preventing algae there are in fact several things homeowners and roofers can do. Why do shingles get algae. Gloeocapsa has the ability to form a protective darkly pigmented outer coating that shields the algae from damaging uv rays.