What Causes Streaks On Roof Shingles

Find out how to remove unsightly black stains from asphalt shingle roofs caused by an algae known as gloeocapsa magma that is spread by airborne spores.

What causes streaks on roof shingles.

Algae grow most often on wood and asphalt shingles or concrete tiles especially if they do not get a lot of sunlight. The black streaks running down roofs are actually a hardy algae called gloeocapsa magma. Over time this algae accumulates developing a black outer coating which causes stains on roof shingles. Algae if left untreated can also cause your shingles to deteriorate over time.

The black roof stains are caused by a form of algae that has been around for years typically found in the woods on the north side of trees or on exposed rocks. This isn t unique to abandoned houses either. It can happen to homes that are otherwise maintained very well but why. But now this black algae is termed a roof shingle algae because of the annoying discoloration on a asphalt shingle roof.

The most common class of roof algae is gloeocapsa magma a bacterium that eats water and expels oxygen. Why do shingles get algae. As the blue green algae accumulate they develop a dark hardened outer coating which results in the black stains you see. Black streaking on roofs is a common problem.

Algae growth on asphalt shingles algae growth may cause discoloration on roofs resulting in brown or black streaks on a rooftop. Almost without fail every photo of an abandoned house would have black streaks on roof shingles. Black streaks on shingles aren t caused by leaking tar. Rather they are caused by a hardy algae known as.

After all asphalt shingles contain limestone which happens to be one of algae s major food sources. Also algae and fungus can grow together to form lichen the roots of which can wrap around and feed on the granules covering the shingles. While the streaks do not cause a great deal of damage they can cause the shingle to age prematurely. The algae feed on the limestone in shingles.

Algae grow and reproduce as they continue to feed on the limestone turning your roof shingles into loose husk over time. While the dark streaks are unsightly experts tell our team that the greatest danger to the roof is from moisture retention or root damage that algae and other life forms can cause. Algae may be mistaken for soot dirt or tree droppings most of which typically produce only localized discoloration. This is what makes those unattractive black streaks on your roof.

Although algae can be found on all types of roofing it tends to be most common on asphalt shingles. Why are algae colored black. Today s homeowner serves cookies to analyze traffic and better serve you.