How to Clean Moss Off House Siding
- 1). Use a water hose to rinse as much of the moss off the siding as possible. Remove any remaining moss with a stiff-bristled brush broom.
- 2). Wear a pair of gloves to prevent skin irritation. Fill a bucket with 1 gallon of warm water. Pour 1/4 cup of trisodium phosphate into the water and stir with a wooden spoon.
- 3). Dip the stiff-bristled brush broom into the mixture. Scrub the house siding where the moss was present with the broom. Begin at the bottom and work your way upward. Continue scrubbing until you have removed all traces of the moss along with any mold, mildew, dirt or other debris.
- 4). Rinse the house siding clean with a water hose. Move the water hose in a steady, back-and-forth motion working from the bottom and moving up.
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