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What are these black streaks on your roof?


These black streaks are called gloeocapsa magma, or GM, more commonly called mold or fungus.  The dark streaks are a type of algae and is an airborne spore that lives off the minerals in some types of roof shingles. Algae thrives in moisture, so it's seen most often on shaded or north-­facing roof slopes that don't get a lot of direct sun.

Why Do I have Moss on my roof?

Moss thrives in a damp, shady environment. For this reason it often occurs on the north side of a roof—since it receives the least amount of sun—or under overhanging trees that provide shade. Over time it can cause roofing to degrade. Homeowners may think moss on roofs is innocuous, just a cosmetic problem or even pretty. Yet leaving it in place can damage the roof and even have disastrous consequences. Research shows that moss needs to be dealt with and the sooner the better .  Once established, it acts like a sponge, soaking up and storing rainwater. Some of that water then wicks up under the shingles through capillary action and soaks into and through the roof underlayment This can cause the underlying wood to become soft and can damage the structural integrity of the framing. You can also develop a serious mold problem.

Can your roof be saved?


Absolutely and without causing further damage. We clean roofs using a non pressure method, the only method approved by ARMA ( Asphalt Roofing Manufacturers Association), which will not void the manufacturers warranty. We also clean roofs for insurance inspectors and back all our work with a 2 year Warranty.

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