Water stains if the discoloration seems to be damp check the attic or ceiling below the roof stain and investigate for a leak.
What causes stains on roof shingles.
The algae feed off of the limestone within the roof shingles.
Causes cures of black brown or green algae staining on roof surfaces.
Roof experts tell our researchers that though other components are being added to shingles to hinder algae growth they still get calls to deal with black marks on relatively new roofs.
As the blue green algae accumulate they develop a dark hardened outer coating which results in the black stains you see.
But now this black algae is termed a roof shingle algae because of the annoying discoloration on a asphalt shingle roof.
Roofing manufacturers have tackled the problem of roof algae by creating shingles containing copper which is deadly to algae.
With each passing year the algae will grow and become more and more noticeable.
Replacing the shingles on your roof just because you have black stains is not necessary however and you should be suspicious of any roofer that suggests roof shingle replacement as the only solution to your algae problem.
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.
Algae stains on roofs.
Look in the gutters for signs of asphalt granules that have washed off and expect to need a replacement.
As it grows it will also trap moisture in the shingles causing them to age sooner than they should.
They say that while shingle manufacturers offer products treated with copper or zinc to inhibit algae growth their effect wears down over time.
The algae feed on the limestone in shingles.
Over time this algae accumulates developing a black outer coating which causes stains on roof shingles.
The black roof stains are caused by a form of algae that has been around for years typically found in the woods on the north side of trees or on exposed rocks.
Light spots on roof shingles dark colored asphalt shingles may appear lighter and patchy as they age.
Btw don t leave those stains on the roof as they will eat away at the shingles and cause the lifespan of your roofing material to decrease by years.
Here we discuss the causes of algae growth on roof shingles the effects of these conditions and how to cure or prevent algae formation on roofs.