12 ON YOUR SIDE: Cleaning your roof of plants and fungi

RICHMOND, VA (WWBT) - 12 On Your Side helped a woman with a roofing mix-up. She's getting a new roof this week, weather permitting.

But the roofing company said roof cleaning is the solution to black-streaks and plants growing on her roof, not the type of shingles.

Once her roof started budding, Denise Butler discovered the wrong roof was installed on her home. She believes roof cleaning damages the shingles.

Roof cleaning is best left to professionals. It's work high above ground and high risk for slipping and falling which warrant police-issued boots.

"When the cleaner is on the roof and it's very slippery up there, these shoes work very well. I can have grip and maneuver and not worry about my life," said Rob Sawyer.

Sawyer's company, American Roof Brite, inspected Denise Butler's roof at the beginning stages of her dispute with the roofer and manufacturer. Denise's roof isn't as bad as some. She just isn't sold on roof cleaning.

"The more times I clean it, the more it's going to deteriorate the shingles. I don't want to spend the money on these cleanings," said Butler.

Chesterfield Extension Agent Michael Likens said roof plants indicate something must change.

"Getting something to germinate on a roof is really not any cause for alarm," said Likens. "If it takes root, then you've got some issues. It will work it's way down into wet wood and take hold. You're looking at some failure of your roof."

He recommends roof cleaning and, like Sawyer, said despite the amount of zinc and copper in shingles, fungus and mold will grow in shade.

"It's floating in the air. Hits the roof. Little mold spores. It germinates. It drops seedlings. That's how you get the zebra stripe that grows on the roof," said Sawyer.

Sawyer has worked on roof tops that resemble underbrush and claims, with his patented technology, even a roof this bad only needs one cleaning. He uses a special detergent and a roof rover.

"We spray it on and as you can see it's lifting the root of the fungus. As we gently rinse it off, the granules are remaining and the shingles are in tact.

"If you clean the roof two to three times with high pressure or bleach, you've lost half the life of the roof," said Sawyer.

Sawyer said power washing destroys shingles and removes the granules. Bleach and caustic solutions dry out your roof and kill plants around your home.

His roof cleanings cost — about 10 percent of what it would cost to replace the roof.

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