What Causes Streaks On Roof Shingles

If you live in a humid area of the country you ve probably seen unsightly dark streaks on asphalt shingle roofs.

What causes streaks on roof shingles.

The most common culprit is actually a blue green algae known as gloeocapsa magma that is spread by airborne spores. Every wonder what causes those ugly black streaks and stains on your roof. This algae growth usually begins as small spots and then eventually becomes visible streaks. 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.

This isn t unique to abandoned houses either. 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. If the streaks don t bother you or you re not ready to invest in a new roof install zinc or copper strips available at roofing centers along the top course of shingles. The most common type is known as gloeocapsa magma also known as blue green algae.

Almost without fail every photo of an abandoned house would have black streaks on roof shingles. It can happen to homes that are otherwise maintained very well but why. Although these dark spots and ugly black streaks on your roof may look like dirt mildew soot or mold what they really are is algae. Dark streaks or roof discoloration caused by algae happens in varying degrees across the u s especially in areas exposed to warm humid conditions.

When rain hits the strips it produces a solution that runs down the roof and keeps algae moss and fungus from growing. The streaks are caused by a type of algae known as gloeocapsa magma. But now this black algae is termed a roof shingle algae because of the annoying discoloration on a asphalt shingle roof. Algae grow and reproduce as they continue to feed on the limestone turning your roof shingles into loose husk over time.

While the streaks do not cause a great deal of damage they can cause the shingle to age prematurely. Though often attributed to an accumulation of dirt defective shingles mold or mildew. Rather they are caused by a hardy algae known as. Black streaks on shingles aren t caused by leaking tar.

Video on how to clean softwash an asphalt shingle roof including where to find. 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 if left untreated can also cause your shingles to deteriorate over time. Causes of black streaking on roofs.