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Denver Roofers Discuss Algae on Roofs


February 22, 2017

Have you ever spotted dark black streaks on your roof? Many homeowners assume these dark streaks are dirt, mold, or mildew, but in reality, this could be algae building up on your roof. How does algae form on your roof? What should you do about it? Here’s what Denver roofers from Big Creek Roofing want you to know:

How does algae get on your roof?

Algae forms on roofs when there is a lot of moisture present. Even if you haven’t had a particularly rainy season, algae can form if there’s a lot of dew on your roof. It can form anywhere, but it’s more common on parts of the roof that are shaded by trees and don’t receive much sunlight. The spores can travel by air, so once one roof in your neighborhood has algae, it’s possible that it will soon spread to all of the other homes in the area. Although algae usually begins as small spots, you probably won’t notice it until it has turned into long, dark-colored streaks. By this time, it’s possible the algae has been on your roof for weeks or even months.

Does algae damage your roof?

Algae won’t immediately damage the integrity of your roof, but it does affect its appearance, especially if you have a light colored roof. A black streak on your beautiful roof can be an eyesore, which is why many homeowners rush to get it removed as soon as possible. If you leave algae on your roof for a long period of time, the moisture within the algae could begin to wear down the asphalt. Also, if you have a cool roof, algae may affect the roofing material’s energy efficiency.

What should you do if you spot algae?

If you see algae on your roof, contact a roofing professional as soon as possible. The algae will need to be washed away using a solution of chlorine bleach and water, but you shouldn’t attempt to get on the roof and apply this solution on your own. Performing any kind of maintenance work or repairs on your roof is risky enough, but algae can make it even more slippery and dangerous.

Some homeowners try to get rid of algae on their own with the help of a pressure washer, but this is not a good idea. Pressure washers should not be used on shingles, because the force of the water can cause some of the asphalt granules to loosen. Always contact a professional before performing any kind of maintenance or repair on your roof.  Learn more about algae and moss prevention and cleaning for asphalt roof systems.

Do you see signs of algae on your roof? Contact the professionals. Big Creek Roofing is the premier Denver roofing company, with a staff that specializes in every aspect of roof maintenance, repair, and replacement for commercial and residential properties. When you hire our team to tackle your roofing project, you can expect on-time and high quality service at a reasonable price. Contact us today to discuss your roofing needs!
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