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What Is Growing on Your Roof?

There’s something growing on your roof. Your formerly fresh-looking roof now looks fuzzy and discolored. You know that whatever is happening to your roof isn’t normal. But you aren’t sure what it is or how to treat it.Your roof, like anything else that’s exposed to the elements, is at risk for a host of problems. When something grows on top of the shingles (or other roofing material), it can leave you wondering if you need to replace the roof or refinish it. Luckily, most stains and streaks are completely treatable. Understanding what can grow on your roof is the first step to solving your problem.Before worrying that your roof has met its end, take a look at common culprits behind this type of issue and what you can do about it.

Roof Algae

Algae grows in your fish tank and in the ocean, right? While algae can grow in watery environments, it can also take hold anywhere that has the right conditions to support it. The warm spring and summer weather, combined with rain, can create the perfect setting for blue-green algae growth.Homeowners often mistake algae for mold or mildew. Even though all of these substances can streak and stain roofing materials, algae is more common than fungal growths. Algae streaks may look scary, but they rarely warrant a roof replacement. Unless you have other underlying issues, such as cracked or aging shingles, it’s likely that you can simply clean the roof.Keep in mind, rented pressure-washers and other DIY cleaning methods are dangerous – to you and your roof. High-pressure cleaning can damage or destroy the roofing materials, especially if your roof is older or starting to show signs of wear. The best option is to hire a pro to completely clean your roof.If you have concerns about the algae returning, adding copper or zinc metal to the roof can stunt the algae’s growth. Discuss workable ways to use metals, such as installing a strip or flashing, with your roofing contractor. Your roofing professional can recommend the best solution for your specific roof and its individual issues.

Moss Growth

If the growth on your roof looks fuzzy and plantlike, that may be due to it being an actual plant. Mosses and other lichens can grow on rooftops in warm, humid climates. When the weather gets rainy, you may notice the green, turf-like carpet growing on top of your home.Even though moss detracts from your home’s natural beauty, the aesthetic issues aren’t the only problems. Moss is like a sponge – soaking in the rainwater as it falls onto your roof. This means the moss may hold the moisture against your roof-causing mold to grow underneath it or the underlying wood to rot. Mold that grows into your attic can result in health issues for you and your family, and rotting wood can cause serious structural damage to your home.If you already have moss, then a professional can recommend a treatment. Chances are that DIY removal won’t completely cure the problem. Like with algae, copper and zinc metals can help to prevent or stop moss growth on your roof. Along with metals, chemical removal agents can clear the moss. Only a reputable professional should use a chemical moss cleaning product or method on your roof. Never attempt to use mossdestroying chemicals on your own.

Mold Infestation 

Mold can cause a host of health issues, ranging from eye and skin irritations to asthma and other respiratory problems. Again, dark stains and streaks on a roof are more likely to be algae than toxic mold. If you’re unsure, ask your roofing pro to assess the growth.It’s more common for mold to grow underneath the roofing materials, where water leaks in and collects. When this happens, repairing the source of the leak is necessary.

Is something growing on your roof? Our team at C&W Roofing, Siding & Window Co. can help. Contact us today for more information.