What Causes Stains On Roof Shingles

But now this black algae is termed a roof shingle algae because of the annoying discoloration on a asphalt shingle roof.

What causes stains on roof shingles.

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. 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. 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. As the blue green algae accumulate they develop a dark hardened outer coating which results in the black stains you see.

Look in the gutters for signs of asphalt granules that have washed off and expect to need a replacement. 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. Light spots on roof shingles dark colored asphalt shingles may appear lighter and patchy as they age. Here we discuss the causes of algae growth on roof shingles the effects of these conditions and how to cure or prevent algae formation on roofs.

Reply thomas boni july 13 2020 at 12 18 pm. The algae feed on the limestone in shingles. They say that while shingle manufacturers offer products treated with copper or zinc to inhibit algae growth their effect wears down over time. Over time this algae accumulates developing a black outer coating which causes stains on roof shingles.

With each passing year the algae will grow and become more and more noticeable. The algae feed off of the limestone within the roof shingles. The algae will worsen and become more noticeable each year trapping moisture and causing premature shingle aging and granule loss. Algae dark stains on asphalt roof shingles the primary species of algae that tends to collect and grow on roofs is called cyanobacteria gloeocapsa magma algae which is contained in and transported through the air.

Causes cures of black brown or green algae staining on roof surfaces. Water stains if the discoloration seems to be damp check the attic or ceiling below the roof stain and investigate for a leak. As it grows it will also trap moisture in the shingles causing them to age sooner than they should.