- 1). Fill a pump sprayer with environmentally friendly, biodegradable moss killer. Dilute in accordance with the manufacturer's directions.
- 2). Climb a ladder to the roof with the pump sprayer, wearing work boots with adequate traction. If necessary, use a harness connected to the chimney.
- 3). Saturate the clumps of moss with the moss killer. Allow the moss killer to soak into the moss for several minutes.
- 4). Bring a garden hose with a high-pressure nozzle and a plastic putty knife up to the roof. Blast the clumps of moss with the spray to dislodge them and wash them over the edge. Scrape off any clumps that won't give with the putty knife. Start on one side and gradually work to the other side to avoid walking on the slippery, wet roof.
- 5). Leave the roof to dry then return to scrub last bits of moss and remaining stains using environmentally friendly, biodegradable roof cleaner and a scrub brush. Once finished, rinse the cleaner with fresh water.
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