- 1). Remove leaves, branches and other debris from the roof. Also remove debris from gutters so moisture will flow quickly away from roofing material after washing.
- 2). Mix a solution of ¼ cup of laundry detergent to 1 gallon of water. Mix until the detergent is well dissolved. Pour into a spray tank.
- 3). Spray the solution to soak the area of the roof where moss has grown.
- 4). Allow the solution to sit for 15 minutes to allow the moss to soften for easier removal.
- 5). Scrub the affected area with a long-handled brush until the moss loosens from the roofing material.
- 6). Rinse the area carefully to remove loose moss and detergent from the roofing material.
- 7). Apply a moss-inhibiting substance formulated specially for roofs to prevent the growth of moss.
- 8). Nail 10-inch-wide tin or other metal strips at the top of the roof incline to inhibit moss growth. These metal pieces release salts that inhibit moss growth. Nail into a rubber gasket to prevent leaking at these points.
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