What to Do With Black Streaks on Your Roof

December 12, 2022

If you’ve noticed black streaks on your roof, it’s most likely algae growing on top of your house. It can be mistaken for mold and mildew, and it’s equally unappealing. Algae growth doesn’t begin when you can see it. In fact, black streaks on your roof likely means that it’s been there for months!

Humid climates around the coast are prime for algae growth. It’s common to see it on top of multiple houses that are close to each other because the spores can be spread by wind or animals. Over time, algae on your roof can damage your shingles or even cause further moss growth. Not to mention, black streaks on your roof most certainly do not add to your curb appeal. Luckily, IBEX is here to help!

Cleaning Algae and Moss Off Your Roof

If you’re thinking of getting rid of the black streaks on your roof, there are a few different chemical treatments that may help. Bleach and water are commonly used to get rid of growth. You can also try using oxygenated bleach or trisodium phosphate (TSP) mixtures.

When cleaning off your roof, it’s important to use your choice of treatment with caution to prevent any further damage to your roof or landscape. Some chemicals can be corrosive to metal or damage wood if used improperly. Be mindful of any water run-off from rinsing off your roof to protect your lawn or plants that surround your home.

NEVER pressure wash your roof. Not only can this spread the algae underneath the shingles, making it more difficult to clean in the future, but it can actually damage your roof and decrease its longevity.

Preventing Black Streaks on Your Roof

As is key to preventing most roofing problems, proper maintenance can help keep your roof streak-free. Algae enjoy shady, moist areas. You can discourage their growth by trimming overhanging tree branches back and allowing direct sunlight to hit your roof. Cleaning your gutters and making sure there is proper drainage will also prevent a moist environment to cultivate algae growth. For homes that are highly prone to algae and moss growth, use some zinc powder on your roof before they get a chance to grow.

IBEX can help you get rid of those ugly, black streaks on your roof. Even if your roof is currently algae-free, we provide maintenance services to help keep your roof in good shape so it can continue to protect your home for many more years.

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