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Understanding and Removing Roof Algae

Roof cleaning

Ugly, black roof streaks are a common sight on Gulf Coast homes. You may even have them on your roof. They look like regular streaks of dirt or runoff, but they don't rinse away when you hit them with the hose. In fact, they seem to get bigger and darker as time passes. As a conscientious homeowner who wants to preserve your home's beauty, quality, and value, you might feel a little alarmed by these strange streaks. Can they be removed, or is it time for a new roof?

Good news: the streaks usually can be removed with professional roof cleaning. Unless your roof is more than 20 years old or has weathered a hurricane or other severe event, it probably doesn't need to be replaced. Still, you probably want to know what's causing those pesky streaks.

What's Causing The Streaks On My Roof?

The streaks are caused by a type of blue-green algae called Gloecapsa magma. They proliferate in hot, humid climates like our own, and they tend to grow on areas of your roof that are shaded or get less sun exposure (north and east-facing panels). Their tiny airborne spores cause them to spread easily between rooftops and to other surfaces. While you'll find these algae growing elsewhere on your property, they're most prevalent on your roof because they thrive on the limestone in your asphalt shingles.

Are These Algae Dangerous?

If you neglect these algae for too long, they can lead to serious structural and health problems. As they consume the limestone in your shingles, they cause granule loss. The UV granules on your shingles are what protect your home from fire and the elements, so when they're gone, your family is vulnerable, and your utility costs literally go through the roof.

Also, as the algae eat the limestone, they can work underneath the shingles, causing them to lift, tear, or come off entirely. When these breaches occur, mold is able to invade interior structures and living spaces. As you're probably well aware, mold infestation is a serious and expensive problem.

Can I Prevent The Algae From Forming In The First Place>

Because of our climate and the airborne spores, it's difficult to avoid algae. However, you can do things to inhibit their growth. You can trim trees to let more sun onto your roof, and you can make sure your gutters aren't backing up and causing unnecessary moisture.

Some people suggest installing a strip of copper or zinc, which is toxic to the algae, just under your roof peak. When it rains, the molecules run down and kill the algae. This tactic isn't foolproof, and when it's not raining, the algae are growing. You can also install copper-infused shingles, but they're costly, so if you're not ready for a whole new roof, you may want to wait.

Otherwise, the very best way to remove and prevent rooftop algae is to have annual roof cleaning by a professional pressure washing specialist.

What Is Professional Rood Cleaning?

Most contractors who do roof cleaning are billed as pressure washers, but the reputable ones won't actually pressure wash your roof because it's too abrasive and can cause more granule loss than hungry algae. If a contractor suggests this method, you may want to keep shopping.

Soft washing is a safer, preferred method for roof cleaning. A gentle soft wash solution is used to dissolve algae and other contaminants. It's proven safe for your roofing and other surfaces, and because the solution is biodegradable and eco-friendly, it won't harm your plants or pets.

Plus, the soft wash solution kills algae at its core, so the treatment is guaranteed to last for at least a couple of years. However, experts recommend having professional roof cleaning at least once a year because even if you can't see the algae, it's growing microscopically on your roof.

Can I Do My Own Roof Cleaning?

Roof cleaning is dangerous if you lack experience or the right gear. Falls can cause serious injury, and undiluted soft wash chemicals can burn you. Also, DIY roof cleaning may void certain warranties and insurance policies. Why take these risks when a reliable contractor like PDUBBZ POW-R-KLEEN is ready to make professional roof cleaning affordable and satisfying for you?

If you want a safer, more beautiful algae-free roof in the North Port area, then please call 941-275-4628 or complete our online request form.