Sometimes They Come Back! How To Effictively Kill Algae Streaks On Your Roof

Algae growing on your roof can cause nightmares. You kill the stuff, but it often returns--like the living dead! Its return is very common if you live in an area with warm, humid summers. Don't let that algae become your horror story; learn how to kill it and keep it from coming back. You can do it by following a few simple tips.

Kill It Safely With Oxygen Bleach

The old standard of cleaning roof algae is to use chlorine bleach, but this can discolor your shingles. Instead, consider using oxygen bleach. You can find oxygen bleach in stores. It is a powder sold in tubs. All you need to do is mix the powdered solution with warm water, spray it on the algae-affected areas, and allow it to soak for about 10 minutes. The water and oxygen ions work to kill the algae, and then you scrub the shingles using a bristled brush on a pole. Make sure to brush downward on the roof and not up; brushing upward can cause damage to your shingles. 

Oxygen bleach containers have instructions for use, so use as directed. Once you're done scrubbing, rinse the roof using a water hose. These products are non-toxic and won't discolor your shingles. 

Keep It Away With Copper Strips

Copper is an effective algaecide. To use copper strips as an algaecide, place strips of copper under the row of shingles closest to the roof's peak. You need to leave a couple of inches of the copper strips exposed so that when it rains it spreads the copper molecules down your roof. These molecules kill any algae trying to make a comeback. 

Zinc strips also work to prevent algae from growing back, and they are less expensive than copper. You use them in the same way. 

Prevent Algae With Good Maintenance

Proper roof maintenance also helps prevent algae growth on your roof. Just doing little things, like keeping the roof free of leaves, twigs, and other organic debris can help reduce algae growth. Leaves and other debris trap moisture on the roof, which increases the risk of algae growth. 

If your shingles are too worn to scrub the algae away, they most likely need to be replaced. You can contact a local contractor who provides residential roof repair to inspect your shingles and determine if it is necessary to replace them. The roofer can also help with cleaning algae-laden roofs and installing metal strips to keep it from growing back. If you decide to replace the shingles, ask about ones made with copper granules blended into the asphalt as a good way to keep algae away. 

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