Guest Post by Joseph Heidler

Yes, those ugly dark stains on your roof are actually a fungus growing, usually gloeocapsa magma to be specific.  It is also a “growing” problem.  Becoming much more prevalent in recent years, this algae is now able to live in more northern climates than in the past. We have the same problems right here on Lancaster, PA homes.

These unsightly stains can generally be removed through careful cleaning with the right methods.  Here is a link to a Washington Post article  on cleaning the fungi from the roof.  Please remember that improper cleaning can damage your roof.  It can also be dangerous to get up there yourself if you are not used to working at heights.  If you think it will be unsafe or don’t know how to proceed, please call a professional contractor.

In an effort to prevent these stains, several manufacturers are now offering algae-resistant shingles.   Here are some links to these products  from Owens Corning and Certainteed.   These shingles have copper or zinc granules embedded in the surface.  These leach over time and inhibit algae growth.  You can even obtain a 10 to 15 year algae resistance limited warranty.  Personally I don’t think too much of the warranties.  Your best bet is to use a quality product with a quality contractor.  If you have any questions about this article or about roofing in general, feel free to contact me at heidler@heidler.com or at www.heidler.com.

J. V. Heidler Co., Inc.  209 Hazel Street, Lancaster, PA  17603

“the best roofers anywhere”

ph 717.291.4405,  fax 717.291.4485