The main reason to clean your roof is to extend the life of your shingles or other roofing material! While algae isn't harmful to asphalt shingles, moss is, according to ARMA. Removing moss from the roof is absolutely necessary to guarantee the proper functioning of your roof. Moss on your roof is not only ugly but allows the shingle to curl up causing damage when there are high winds.
Price: There is no set price but the price for cleaning a roof starts at $450