There’s a lot of talk about the common roof stains or roof streaks that appear all over Northern Virginia and across the southeast.
That would be Gleocapsa-Magma, it is an airborn algae stemming from cyanobacteria. It is the cause of the staining you see on many roofs along the region. Mix with humidity, lack of sun (more shade) and a food source, you will have a perfect petri dish for the organic growth of Gleocapsa-Magma (AKA a asphalt shingle roof)
Where to expect the airborn algae to grow?
- In climates that get warm and humid
- On north facing sides of roof
- On parts that are blocked by shade
- Also where there is excess moisture or where some downspouts dump onto the shingles.
What’s the “food source?”
Since all living organisms need some sort of food, the algae does too. Asphalt shingles are constructed of parts of limestone, this is what the growth feeds on, eventually eating through the shingle.
Moss and lichen have similar characteristics.
For information on roof cleaning, click here