Asphalt Shingle Roof Cleaning
- 1). Equip a pressure washer with a general-purpose cleaning tip, such as a 25 degree tip. The pressure washer should develop at least 2,500 pounds per square inch (psi) of pressure.
- 2). Stand at the top of your roof where it slopes downward. Start by cleaning the one foot square area just below the slope with the pressure washer on full blast and kept within six inches of the asphalt shingles.
- 3). Move to the next one foot square area downward and clean that area with the pressure washer. Continue this process until you have cleaned the entire roof.
- 4). Use a scrub brush on any stubborn moss or algae that is still stuck to your asphalt shingles. Spray them down with the pressure washer once you're done scrubbing.
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