The most effective method of cleaning algae and moss from a roof is with a 50 50 mix of laundry strength liquid chlorine bleach and water.
Cleaning moss off roof.
Hose off and brush all moss loose from your roof shingles.
Climb up to the roof and begin scraping off dead moss from the shingles using a putty knife or painter s 5 in 1 tool and working from the bottom up.
Its recommended anyone cleaning moss off a roof should do it on a cloudy day.
Most roof cleaning products require at least 20 minutes for it to absorb into the moss.
If you re going to use one of these solutions to remove moss climb down from the roof and cover any landscaping that s in the line of fire with a plastic tarp.
Apply w ith a sprayer and allow the solution to dwell on the roof surface for 15 to 20 minutes and then rinse thoroughly with low pressure water.
Scrape off the moss.
Apply cleaning solution only after the roof and moss are thoroughly wet.
When applying roof cleaning products onto a roof on a hot sunny day it will quickly evaporate and you won t get the desired result.