How to Get Rid of Algae on Your Roof

We all know that roofs can collect dirt and leaves, but did you also know that it can trap algae, too? It may be hard to notice depending on your roof’s structure, but it can easily build up various types of algae, lichens, and fungi bacteria over time. If you notice that your roof has a blue-green tint, you likely have an algae issue. And, if it’s left untouched, the algae can die and leave nasty dark stains on your roof. Let’s take a look at what causes roof algae and what can be done to get rid of it.

What Causes Algae Buildup?

According to The HTRC, black streaks caused by black algae is called “Gloeocapsa Magma” and is typically chalked up to dirt buildup or defective shingles — but that couldn’t be further from the truth. In fact, algae tends to thrive in certain environments like hot, humid atmospheres, shady or damp areas, and under big trees which causes the streaking. Additionally, since the algae on roofs are living, they need nutrients to survive—and sadly, the limestone filler in many shingles gives it the nutrients it needs to grow. In many cases, all it takes is one algae spore to land on your roof and make itself at home. If your roof is shaded or you live in a rainy climate, it could elevate the problem. Even if your home isn’t in a shady or wet area, clogged gutters can also contribute to algae on the roof, so it’s very important to schedule routine gutter cleaning as well.

How Algae May Affect Your Home

Aside from an undesirable appearance, algae on the roof may cause other problems as well. For example, it can devalue your home, damage underlying roof materials, and lead to wood rot and mildew issues. You can learn more about wood rot causes and prevention at our blog. Lastly, if you allow roof algae to fester, it can damage structural integrity and threaten your family’s health. Oftentimes, when algae turns into mildew, it can become a harmful toxin to breathe. For instance, according to the CDC, mold exposure may lead to asthma in young children, particularly for those who are genetically susceptible.

How to Prevent Algae 

Prevention is the best way to ensure your home is protected—make your roof an unhealthy place for algae spores to grow by increasing the amount of natural sunlight that hits your roof. You can do this by trimming back branches or trees that provide excess shade. Additionally, Feldco Roofing suggests other measures like eliminating standing water, getting your roof washed regularly, installing an algae-resistant roof, and getting new shingles. Lastly, we encourage you to schedule routine exterior maintenance with Labor Panes to ensure there’s no algae buildup over time.

Getting Rid of Your Algae Problem 

If you’ve already identified that you have an algae issue, it’s important to deal with it quickly. Once again, we encourage you to call the professionals because letting the issue linger can lead to further damage, or worse, health concerns for those without the proper personal protective equipment. If you’d like to try to take care of the algae yourself, we recommend applying a 50:50 mix of laundry strength liquid chlorine bleach and water, then spraying it off with a low pressure washer. 

Whether you’re concerned about the potential of having algae on your roof, or you’ve already found it to be an issue, it’s important to understand what you can do to protect yourself and your home. If the situation has gotten so bad that you need a roof repair or replacement, please find a reputable licensed roofing contractor in your area. But, if you know your situation can be remedied with proper maintenance, contact us to get a free quote.

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