Roof Cleaning is nothing new. The large majority of the population in the United States has a roof made of asphalt shingles. These asphalt shingles adhere to the roof and protect the house from water infiltration, temperature, and uv light. Asphalt shingle roofs last 10-20 years depending on the weather of the area they are in. The asphalt shingles have a granular coating on them to further insulate and protect the roof of the house. The granular coating, usually made of rock, hold mold and mildew. If left unchecked, the mold and mildew will continue to grow and expand over the roof. This layer of mold and mildew holds water, which leads to premature shingle degradation and wood rot. This is a problem for the homeowner and that is where roof cleaning comes in.