blue-green algae - Keil Tree

Blue-Green Algae on Your Roof Is an Eyesore

Whether you’re a homeowner or a roofing professional, you’ve probably seen it before: blue-green algae. This “stain” isn’t what most people think it is, and as a result, any discoloration on your roof should be reported to your chosen contractor in order to get it cleaned up the proper way.

How to Avoid and Remove Blue-Green Algae

This bacteria is called blue-green algae, but it appears in colors of dark browns and blacks up on your roof. Why? Because “you’re looking not at the algae, but at the hard, dark coating it generates to protects itself from damaging UV rays.”

So, how did this irritating pest get up onto your roof? Most likely, it traveled there on the wind from one of the nearby houses, since this is how it’s said to spread. Like many other things related to this bacteria, it does well in moist areas and “feeds” from microscopic bits in the air. It’s true that this blue-green algae causes no real harm to your roof, and won’t eat through it or anything else, but you may simply not like the look of it.

This is understandable. If you’re trying to sell your home, for example, the algae can negatively impact curb appeal. Additionally, since it darkens to protect itself, that new, dark color could make it so your roof absorbs more heat, rather than reflecting it, which makes your home less energy-efficient than before, even if you have a cool roofing system beneath the algae layer.

“The good news is that Gloeocapsa magma is both treatable and, if you plan ahead, preventable.” There is a variety of cleaning products that can help to make this unpleasant layer vanish. Still, make sure that you know what kinds of solutions should and should not be used on your roof (solutions with bleach, even diluted, are not right for all roofing types).

To prevent the growth of blue-green algae, consider copper (or zinc) strips, which are installed at the ridges of your roof. More than that, just practice regular roof maintenance to keep things clean and clear, and you’ll have no more of this pest in the future.

For those who need a serious roof cleaning or maintenance, get in touch with Cox Roofing. You’ll be able to work with a Baltimore County roofing business that has your best interests in mind and which has over thirty years of experience.


Cox Roofing:

Cox Roofing is a full-service, certified roofing contractor providing residential and commercial roofing services to the state of Maryland, with a particular focus on Baltimore City, Baltimore County, Harford County and Howard County. We pride ourselves on our personalized service which transforms your property into the residence or business of your dreams. Get in touch for your free estimate today.

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