Algae and Mold Asphalt Shingles
Algae and mold asphalt shingles damage may appear as black, brown, or gray stains on the asphalt roof shingles.
A lot of the cases for roof stains come from an algae strain called "cyano bacteria gloeocapsa magma" which is very widespread problem on roof shingles and tiles.
Some coloring of the shingles may be due to other factors, such as shingle leakage.
The strain of algae that may be in question, however, feeds on organic crushed limestone that is present in modern day shingles (but not on the much older ones that do not use limestone).
It is possible to find large concentrations of fungus, mold on shingles, and roof mildew growing on roofs almost throughout the country, but especially in those states which have higher levels of moisture in the air.
Fortunately, removing the stains is possible and there are contractors available to do such work in most bigger cities and in many smaller ones.
Factors that affect how quickly and how severely these strains appear on the roof include weather and how the roof is maintained, as well as the type of asphalt shingles used.
To reproduce on the roof, the algae needs ideal weather (of heat and moisture) and algae nutritional elements.
Of these factors, shingle mold and algae stains get the required heat from the sun, moisture from rain and dew, and nutrients from the limestone fillers in asphalt shingles.
Because these factors are inevitable, the answer may lay in periodical cleaning of the roof shingles, something which many order from contractors on an annual basis, to remove roof mold and algae and return the original curb appeal of the roof.
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