What’s That Growing On My Roof?

Step back and take a good look at your home from top to bottom. Does your roof look like it used to when it was new? If your answer is no, if you see black stains and it looks as if something is growing up there, what do you do next? Is it time for a new roof?

First, let’s discuss what could be on your roof.

Does your roof have algae, moss or lichen?

Listed below are the most common fungi and bacteria crawling above your crawl space.

Bacteria (Black Streaks) – The black stains commonly seen on roofs is a Cyanobacteria called Gloeocapsa Magma. Most refer to this as “roof algae,” but in fact it is a bacteria.

This roof bacteria is transported through the air which is why it has moved from humid Southeastern States all through the Midwest rapidly after the 1980s (prior to this time roofing material was made of a different material that didn’t provide as much “bacteria food”).

Once the organism lands on your roof it begins to feed on the limestone granules, which is a filler found in today’s fiberglass shingles. The streaks form as the rain falls, pushing the bacteria further down the roof each time. Before long the stains are pushed all the way down the roof, causing streaks, as well as spreading to the left and to the right. This spreading and feeding process is destructive to the roof and causes shingle decay, an inability to reflect UV-rays, and significantly ruins curb appeal.

MossMoss – On highly shaded areas of the roof, particularly near tree cover, moss can begin to grow. Moss acts as a sponge, keeping the roof from being able to dry out. In addition to this, the moss clings to the roof which makes it dangerous to remove by hand since you run the risk of pulling up granules along with it.

LichenLichen – This double fungus appears as white, yellow or even orange spots on the roof and is the most aggressive of the three infestations. Because of its aggressive nature lichen will eat the roof to the point of causing pitting.

Does your roof have algae, moss or lichen?


What To Do If You Spot These Organisms on Your Roof?

Call the Pros! Clean Pro Exteriors will come to your home and analyze the damage done to your roof. Chances are good that your roof only needs maintenance and doesn’t need to be replaced!

Many homeowners assume their roof needs to be replaced and end up wasting thousands on a new roof. However, usually this is not the case at all. The best way to tell if your roof is in need of being replaced is to check your shingle warranty. Most shingles today have a 25 year to 40 year lifespan. If your shingles are still within this time period, save your money, it only needs a cleaning.

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Locations in North Carolina Serviced by Clean Pro Exteriors:

General service area for Pressure Washing and Roof Cleaning: Rocky Mount, Greenville, Winterville, Wilson, Nashville, Tarboro, Pinetops, Scotland Neck

General service areas for Cedar Shake Roof Cleaning:
Rocky Mount, Greenville, Raleigh, Wake Forest, Holly Springs, Cary, Chapel Hill, Hillsborough, Nashville, Wilson



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