Bleach is caustic to the roof and plants. At most, the bleach should be 50% of the solution. Lye products also work, but are caustic to the skin and should only be handled while wearing protective gear. If you’d rather buy a cleaner from the store, look for a detergent specifically made for shingled roofs. [5] X Expert Source Allen LeeHome Improvement Specialist Expert Interview. 10 July 2020.
Power washers should never be used. They will wear away your shingles.
A broom can also be used to scrub in cleaner. Use a broom of medium-stiff bristles and apply little pressure so you don’t damage the integrity of the shingles. [8] X Research source
Installing these strips can puncture sealant on the shingles, so it’s best to do this when placing a new roof. Stringing copper wire may work instead.
