Moss on your roof is a bad sign. The plant growth will continue and creep under the edges of your asphalt shingles. This action elevates them and allows water to penetrate underneath the shingles. If you’ve noticed this issue, it’s time to learn how to clean moss off a roof. The problem needs your attention as the deterioration of the shingles will only accelerate and your roof may eventually leak.

Before learning how to clean moss off a roof, find some nonskid shoes and get a safety harness if you have a steep roof. When mounting a roof, you should use an extension ladder that extends beyond the edge of the roof. You should also resist any temptation to use a pressure washer on the roof. In the presence of moss growth, the shingles might already be in a delicate condition. High-pressure spray can damage them further.

How to Clean Moss Off a Roof Step by Step

1. Select a moss and mold remover cleaning product meant for roofs. You can buy a commercial product or mix a homemade formula of 1/2 cup dish soap to 2 gallons of water.
2. To protect plants, patios, and porches beneath the work area, spread drop cloths.
3. Place the ladder on stable ground and climb on the roof.
4. Begin by spraying the shingles with just water.
5. Start above the mossy area and work downward so that water is not forced under the shingles.
6. Loosen clumps of moss with the spray.
7. Fill a pump-action spray bottle with the cleaning product.
8. Return to the area above the moss growth.
9. Spray cleaner in a small section.
10. Scrub the spot where you applied the cleaner gently.
11. Continue working downward as before so that you are not forcing up the edges of the shingles.
12. Consult the directions for the commercial cleaner that you used to see if you must rinse it off.
13. When rinsing, start at the top and work down.
14. If you used a homemade cleaner, go ahead and rinse it off.