The algae feed on the limestone in shingles.
What causes dark stains on roof.
It is most widespread in the eastern united states and is commonly found on roofs with northern exposure.
As the blue green algae accumulate they develop a dark hardened outer coating which results in the black stains you see.
Other causes of roof discoloration.
This job goes much faster if you can borrow or rent a 12 volt diaphram garden sprayer with a large tank and a slew of hose preferably on a reel be sure to wear rubber boots plus gloves and stay upwind while applying.
To identify a roof leak you should look for the obvious factors like missing or damaged shingles roof tiles torn flashings or loose screws on the exterior of the roof.
Once you identify the leak have someone fix it before you intend to remove the water stains so that the stains do.
Although these dark spots and ugly black streaks on your roof may look like dirt mildew soot or mold what they really are is algae.
While the streaks do not cause a great deal of damage they can cause the shingle to age prematurely.
Quite a few other issues can cause stains on a roof.
Rust or chimney soot stains red or brown rust stains around chimneys is a common roof stain.
The streaks are caused by a type of algae known as gloeocapsa magma.
The black mold like stains and streaks that appear on roofs particularly light colored asphalt shingles is actually a blue green algae gloeocapsa magma.
The area can be cleaned and.
Here is a diagnostic guide to types of stains and staining materials found on roof surfaces black red green brown or other coloured stains on asphalt roof shingles or on other roofing materials need first an accurate diagnosis of the stain cause and then proper steps to remove the stain or to prevent future staining on roof shingles surfaces.
The black streaks running down roofs are actually a hardy algae called gloeocapsa magma.
The most common type is known as gloeocapsa magma also known as blue green algae.
Dark streaks or roof discoloration caused by algae happens in varying degrees across the u s especially in areas exposed to warm humid conditions.
Roof leaks are the main cause of water stains on the ceiling.
The algae feed off of the limestone within the roof shingles.
Here are some clues to follow.
Over time this algae accumulates developing a black outer coating which causes stains on roof shingles.
If your household water pressure isn t enough to generate the proper nozzle pressure at the jets the manufacturer recommends boosting it.