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Black Stains: How to Handle Roof Algae

Black stains are common on roofs in humid climates and usually there is no reason for Roswell homeowners to be concerned about it. The culprit of black stains is a type of algae that grows when moisture in the air goes unchecked on the roof. There are simple ways to preserve curb appeal and handle this problem.

Spotting Roof Algae

Algae on a roof looks like it is casting a shadow over certain areas of your shingles. You may even see moss, which is another product of humid conditions. On a roof with copper flashing around a chimney, you sometimes see these black spots in areas away from the flashing, as metals like copper prevent algae from growing.

Though the airborne algae does not shorten the lifespan of shingles, most homeowners consider it an eyesore that needs correcting— especially when you have light-colored roofing. Unless you were planning on complete roof replacement, your choices come down to cleaning or adding metal strips to kill the algae on contact.

Removing Roof Algae

When applied with proper force, chemical cleaning solutions can make the black stains disappear quickly. Roof maintenance experts usually handle the job with bleach or another chemical that's proven to be effective on algae. One thing that makes the job tricky is the landscaping surrounding the home. Without proper care, chemical cleaners can hurt or kill plants. Cleaning crews will prepare any plants that may be affected to avoid this.

When you live in Cobb County and neighboring areas, this solution is not permanent. Algae will reappear in time. Roofers may add strips of copper or zinc near the top of your roof to protect against any new growth. With every rainfall, the water washes particles from the metal stripping down the roof to keep it free of algae. If you are replacing shingles, ask your roofer about algae-resistant types that are now commonplace in Southern homes.

Roof algae is unsightly, but there is no reason to let it bother you. Contact Findlay Roofing to remove the black stains. They'll provide recommendations for keeping your roof looking great for the long haul.

Photo Source: Flickr

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