What Causes Black Stains On Roof Shingles

While the streaks do not cause a great deal of damage they can cause the shingle to age prematurely.

What causes black stains on roof shingles.

Spray the black stains first then the entire roof so the stains get a second dose. Over time this algae accumulates developing a black outer coating which causes stains on roof shingles. Replacing the shingles on your roof just because you have black stains is not necessary however and you should be suspicious of any roofer that suggests roof shingle replacement as the only solution to your algae problem. The algae will worsen and become more noticeable each year trapping moisture and causing premature shingle aging and granule loss.

Mix the soap and water well first then add the bleach. Algae is more likely to grow on shaded roof sections probably the cause of black stains on the lower roof in the photo at above right while asphalt shingle bleed through stains more often appear to emanate from single points regardless of sun or shade exposure probably the cause of stains in the photo at above left. Roofing manufacturers have tackled the problem of roof algae by creating shingles containing copper which is deadly to algae. When that happens it is generally caused by mildew algae mold or dirt stains.

These roof invaders require a moisture rich environment usually. Black streaking on roofs is a common problem. Here is a diagnostic guide to types of stains and staining materials found on roof surfaces black red green brown or other coloured stains on asphalt roof shingles or on other roofing materials need first an accurate diagnosis of the stain cause and then proper steps to remove the stain or to prevent future staining on roof shingles surfaces. The streaks are caused by a type of algae known as gloeocapsa magma.

Black marks became a problem about 20 years ago when manufacturers began adding limestone granules to add weight to material used to coat shingles. Algae dark stains on asphalt roof shingles. This will cover 200 sq. Roof experts tell our researchers that though other components are being added to shingles to hinder algae growth they still get calls to deal with black marks on relatively new roofs.

It is not uncommon for roof shingles to turn black over time. The black spots discoloring your asphalt roof are more than likely the pervasive and prevalent algae known as gloecapsa 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 shingles are exposed to a lot of wear and tear as extreme heat sun wind and precipitation come into contact with them.