Getting Algae and Moss Off the Roof
What are those ugly black streaks on my roof and how do I get it off?
You are not the only one asking this question. These black streaks are actually is actually a blue-green algae called Gloeocapsa magma. It actually is doing no harm to your roofing it is more of an eye sore than anything.
So there are a couple ways you can approach this problem.
This issue is usually more apparent on light colored shingles. We have had some people completely fed up with the look of this algae and have opted to remove the shingles for new darker shades. Darker roofing material won’t prevent the algae from returning, but it is less apparent on darker colors.
The more cost effective solution is to spray wash the roof with a 50 percent mix of water and bleach to get rid of the algae. Whatever you do, don’t use a pressure washer as it could damage your shingle; Instead, use a sprayer with moderate pressure. Soak the roof first with clean water then apply the solution mix. After the solution has been applied, let it sit for 15 - 20 minutes before rinsing with clean water. Be sure to protect your plants as they don’t fare well saturated in bleach. We suggest spraying you plants with water before treatment because it will protect them.
To keep the algae from coming back, insert 6-inch-wide strips of zinc or copper under the row of shingling closest to the roof peak, leaving an inch or two of the lower edge exposed to the weather. That way whenever it rains, some of the metal molecules will wash down the roof and kill any algae trying to regain a foothold on your shingles.
If this is a service you are interested in, feel free to give us a call!