How Blue-Green Algae Causes Damage to Asphalt Shingles

The black or brown streaks you’re seeing on your roof don’t indicate that there is a growth of mold, mildew or moss. They also don’t mean that the asphalt shingles are deteriorating and need replacement. These dark stains are actually protective UV coating created by the small bacteria, Gloeocpsa magma, or “blue-green algae.”

Read on to learn more about roof algae growth from your trusted commercial and residential roofing contractor in New Jersey, Dior Construction.

Blue-Green Algae

Blue-green algae spreads via the wind, which means if nearby houses have it, there’s a good chance your home is also exposed. They favor humid and moist environments and harbor nutrients from dust. These microorganisms usually settle on the north side of the roof where there is less sun exposure and more moisture.

Roof Algae and Asphalt Shingles

Asphalt roofs have limestone that makes them heavy and durable. Blue-green algae slowly consume the limestone over time.

The more dark stains these algae create, the more your roof loses its reflective ability. The roof will absorb more heat from the sun which will radiate to the house, causing higher cooling expenses.

It is just the first line of organisms that can infest your roof. Blue-green algae can work together with a fungus to create lichen. Soon, your roof will have moss, forming a thin layer of soil that can collect seeds dropped by birds. Eventually, tiny bits of grass will be growing on your roof.

Worst case scenario: you may have to replace your shingles. Make sure to hire a reliable roofing contractor like Dior Construction, as we are experts at asphalt shingles installation. We’ll assure you that your purchase is protected with our lifetime warranty coverage.

Treatment and Prevention

If you have blue-green algae on your shingles, you don’t have to worry because there are different ways you can rid your home of these organisms.

There are cleaning solutions consisting of 50/50 chlorine bleach and water that you can use to remove stains and stop algae growth. When applying these to your roof, make sure you’re wearing safety gear, rubber gloves and eye protection. Be very careful as the solution may make the roof slippery.

Roof maintenance can prevent the growth of blue-green algae. Expose your roof to the sun more by trimming tree branches and cleaning debris. Make sure the gutters are not clogged to avoid water buildup. You may also use copper and zinc strips and install them at the roof ridge where rainwater will carry algae-preventing ions all over the roof.

If you need residential roofing services, Dior Construction is always here to help. Don’t wait until your home’s exterior problems affect your indoor comfort. Call us at (201) 470-5077 or complete our online form to learn more about our products.  We cater to homeowners in Bergen County, NJ.