Why are There Black Stains on My Roof?

Did you know that those black streaks are actually a type of bacteria called Gloeocapsa Magma? Did you also know that if left untreated, it will cause damage to your roof, requiring a premature roof replacement?

Let’s answer some commonly asked questions about Gloeocapsa Magma, and other organisms that live on roofs.

“So, what causes this stuff to grow on my roof?” 

Since the 1980s, roofing manufacturers have been using limestone in asphalt shingles as a filler material for the product. The porous limestone allows the shingles to hold more moisture, along with living organisms. This results in a perfect environment with plenty of food for Gloeocapsa Magma, lichen, moss and other algae to thrive. The Gloeocapsa Magma begins life as one spore that lands on your roof from a nearby tree or even from a neighbor’s roof, then begins to multiply and spread. The rain drags the spores down the roof, spreading growth and creating an ugly streaking appearance.

“Well, what’s so bad about these little organisms living on my roof, they can’t hurt much can they?”

Actually, yes! Since they feed on the limestone in the shingles, these organisms are quite literally eating away at and breaking down your roof. This causes granule loss from the shingles over time, leading to premature replacement earlier than expected. It’s also a huge eyesore to what may otherwise be a beautiful home. A roof in poor condition is likely to reduce curb appeal, your home’s resale value, and more. Not to mention, many are unaware of the fact that most homeowners’ insurance companies will require that a roof be in good condition, because a roof that is unkempt may be reason enough to increase your premiums or drop your policy altogether. 

“So how do we get rid of it?” 

Fear not, all of these damaging organisms can be safely removed, and we will make sure of it. Preserving the integrity of your roof and restoring your home’s curb appeal is of the utmost importance to us here at Deck Teck. The process requires specific roof treatment equipment, which applies a chlorine-based solution onto your roof at a low pressure. The amount of water pressure used on a roof should be as little as possible, so as to avoid damage. Some contractors may opt to use a high-pressure washer netting immediate results, but at the expense of further roof damage. Our dedicated equipment uses less pressure than a typical garden hose, so there will be no damage done to any roofs we clean. You’ll gain peace of mind knowing that you are extending the lifespan of your roof and saving thousands in future repairs and replacement costs.

“Will the treatment hurt my plants and my lawn?”

While chlorine does have the potential to cause damage to plants and surrounding areas if used carelessly, we ensure safe handling and application of the product, preventing any unintended harm to homeowners’ property. Rest assured, our trained experts will deliver safe and effective results. 

“What if I have moss or lichen on my roof?”

If there is any moss or lichen growth present on a roof, our treatment process remains nearly the same. Frequently though, when moss is present, so are leaves, pine needles, sticks and other debris. We remove the majority of this debris using a leaf blower prior to applying our chemical treatment. This ensures that the chemical can effectively penetrate the organisms. The biggest difference in treating this type of growth, is the time that it takes to achieve the final result. Larger organisms such as moss and lichen have much more developed root structures clinging onto the roof. After treatment, the chemical begins to kill the moss and prevent any future growth, signified by it turning white. A few weeks later the roots will begin to dry up and release from the roof. Rain will then assist the removal process the rest of the way, washing the dead organisms off the roof. This whole process can take anywhere from a few weeks up to 6 months or more depending on how developed the growth was. Some roofs with heavy amounts of growth will require a re-treatment after a few months to remove any remaining organisms.

Don’t wait until your roof is damaged beyond repair! Contact us for a free estimate to clean your roof!