How to Clean Algae From the Roof

Algae on your roof poses no risk to your shingles but can be quite an eyesore. Algae thrives in humid conditions where there is moisture in the air. If trees cover your roof or part of it, you are also more prone to algae developing. Algae can be prevented and effectively treated with oxygen bleach and water.

Things You'll Need

• Oxygen Bleach
• Water
• Bucket
• Pump spray
• Hard-bristled push broom
• Garden hose

Instructions

How to Clean Algae From the Roof

1. Mix 1 qt. oxygen bleach and 1 gallon of water in a bucket, and pour it into the pump-type garden sprayer. Mix the solution well. It's important to use oxygen bleach because it will not discolor your shingles and is not toxic.

2. Begin spraying the solution until the roof is saturated. Allow the bleach mixture to set for at least 15 minutes.

3. Use a hard-bristled push broom to scrub the shingles clean. You may have to re-wet areas of the roof with the solution.

4. Rinse the roof using a garden hose with spray nozzle. If the algae is still visible on the roof, you may need to treat it several times.

Tips & Warnings

• It's best to treat your roof for algae on a cool, cloudy day to prevent the solution from drying up too quickly.

• Wet roofs are very slippery; be sure to wear rubber soled boots or sneakers for maximum traction.

References

• Prevention & Treatment of Algae on Roofs