What are these black streaks on my roof?

Gloeocaspa Magma

You will find black streaks on older roofs are caused by a bacteria called Gloeocaspa Magma.  It travels in the wind and tends to thrive in shady parts of the roof or areas with lots of trees.  This bacterium is often referred to as blue-green algae and it feeds on limestone which is used as a filler in shingles.

Clean Your Roof

Having your roof cleaned by a professional can bring back your roof’s original color, but this will need to be repeated periodically.  Make sure the company cleaning your roof is using a soft chemical cleaner.  Using a power washer on a shingle roof can damage the roof by removing the granules from the shingles.

The Negative of Black Streaks

Are black streaks a problem?  Black streaks can have a negative effect on your home’s overall curb appeal.  This can make your home difficult to sell and might be a red flag for insurance companies concerned with the lifespan of the roof.  It can shorten the life of your shingles because repeated washing and foot traffic can cause damage to the roof.

Algae Resistant Shingles

Installing Algae resistant shingles is the best long-term solution to ugly black streaks on your roof.  GAF utilizes long lasting time-release algae-fighting technology.  The Timberline HDZ and Timberline UHDZ have thousands of copper microsites that release overtime and fight algae growth.   It works so well; GAF offers the StainGuard Plus Algae Protection 25- and 30-year limited warranty.

Call Bayside Exteriors today to ask what can be done to prevent black streaks on your roof.

302-200-7663

Author

Craig Cameron

Bayside Exteriors