What Causes the Streaks on my Roof?

Have you taken a look at your roof lately? Did you see some dark streaks on your roof? Do you know what causes the streaks? What can you do about them?

A recent article by North America’s largest manufacturer of residential roofing and commercial roofing — GAF — detailed just what causes the discoloration on your roof and what you can do about it.

There is a tiny bacteria called Gloeocapsa magma, also called “blue-green algae”, that causes the dark stains. It’s not the algae that you are seeing on your roof, but the dark coating that the algae produces to protect itself against UV rays from the sun. The algae lives on nutrients from dust in the air. Most of the time you will find the stains on the north and west sides of your home, where the roof tends to stay a little cooler and moister.

The algae is airborne and usually travels from one house to another. Chances are that if you see one roof in your neighborhood with the blue-green algae stains, there will be others in the neighborhood with the same problem. Once you are aware of theses stains and what they are — you will be surprised how many homes with these type of stains that you will see as you drive around the area surrounding your home.

There are various thoughts on if this algae actually does any damage to your roof, or if it just stains the roof and makes the shingles on your house look unpleasant. Some roofers may try to tell you that it’s time for a new roof when the stains appear, however, that may not be the case.

The good news is — there is a way to remove these stains! At Roof Cleaner we use the process that is recommended by the shingle manufacturer. Do not use high-pressure washing systems on your asphalt roofing. Those high pressure systems can damage your shingles.

Give Roof Cleaner a call to remove the Streaks on Your Roof!

Roof Cleaner has years of experience in removing these stains from area roofs. We have been cleaning roofs in West Michigan since 2008. Give us a call for a FREE roof cleaning consultation. Our phone number is (616) 240-3465.

To read more about blue-green algae and the stains on your roof, here is a link to the article from GAF.

Streaks on Roof