How To Treat Black Streaks On Your Asphalt Roof

You should inspect your asphalt roof every summer and make sure that none of the shingles are damaged and that nothing is growing on your roof. If you noticed black streaks on your asphalt tiles while inspecting your roof, you have an algae problem. Luckily, this is a problem that you can easily address and prevent from happening in the future. 

How The Algae Made Your Roof Its Home

The black streaks on your asphalt roof are actually algae. The algae gets on your roof via spores that are carried in the wind. If your roof is wet and the conditions are right, the algae spore will make your roof their home. You'll know that the algae has taken root in your roof when you see those black streaks. 

2 Ways To Get Rid Of The Algae

Once you have spotted and identified the algae on your roof, you need to kill the algae. 

Household Bleach

One way to kill the algae on your roof is with regular household bleach. You'll want to make a diluted mixture that is half water and half household bleach. You'll want to spray the mixture onto your roof using a spray bottle.

You'll know that the mixture has done its job when the algae turns a white color. Once it turns white, use a hose to spray off the solution. Don't use a pressure washer — the pressure is too high and can cause damage to your shingles. 

Oxygen Bleach

You can also use a mixture of oxygen bleach and water to clean your roof. Oxygen bleach is essentially bleach in a powdered form. Mix some of the powdered bleach with water, and apply it to your roof just like you would with the household bleach solution.

Once again, when the black algae turns white, it's time to rinse off the solution.

If plants are growing right under the edge of your roof where the bleach solution will fall, spray them with water before you spray off your roof. This will help prevent the bleach from sticking to them. After you spray off your roof, spray your plants again to ensure that the bleach is not sticking around and harming your plants. You should also warn family members or others visiting to not walk around the house while cleaning the roof as the solution might drip onto them as well.

Make sure you clean the algae off your roof right away to prevent further damage. If you have some time, apply the mixture to your roof this weekend. If you find there is damage to your roof that you can't repair on your own, make sure to contact a business like US Roofing.

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