Have you ever noticed those black stains or streak marks on the roofs of most Cleveland homes? At first glance it may look like abstract shapes or shadows, but it is actually clusters of the bacteria called gloeocapsa magma. Many people may mistake this bacteria for algae, however, closer examination can reveal the distinct difference in texture and color between the two. This bacteria is a species of the cyanobacteria which generates an oxygen gas when mixed with water. Geographic locations that are subject to humid weather or frequent rain storms are more susceptible to gloeocapsa magma and the damage it can cause to your roof. Homes that have fiberglass shingles are also more susceptible to this bacteria forming because these shingles are filled with limestone; a material that gloeocapsa magma uses as energy(eats) to spread.
Although this bacteria can formulate in any humid or moist enviroment, the bacteria has become most common in the southeast portion of the United States. Statistics show that cases of gloeocapsa magma are becoming more frequently reported around the states of the north east as well. Once this bacteria formulates it can spread very quickly, covering your entire roof in just a few months, if not treated early. It can be a hassle to get rid of entirely, as leaving just one spec of bacteria is enough for it to generate more spores and start to spread again. In very heavy cases of gloeocapsa magma, homeowners have reported spending hundreds of dollars to have the issue professionally handled to avoid repetitive treatments.
There are some options you can try in attempts to avoid the bacteria from formulating. Most of these will not work. I’ve cleaned quite a few roofs that had the zinc strips installed. Putting any type of permanent coating on you roof is not a good idea becuase it will void your roof’s warranty. The best that you can do, would be to keep your roof as dry as possible. This would involve removing tree branches or whole trees so your roof stays in the sun as much as possible.