When hiring a company to clean your roof, consider this advice, gathered by our research team, which talked to multiple highly rated roofing experts:
—Make sure the cleaners don’t use high-pressure washing systems, which can remove granules coating shingles, and lower their life expectancy.
—Ask what kind of cleaning solution the company uses. One highly rated roofing expert said he uses a chlorine-based chemical wash with a soaping agent. Also, make sure the company has a plan for preventing possible damage to your home or landscaping from runoff. That same roofing expert said he has one worker apply the cleaner while another saturates nearby areas with water to prevent damage.
—Ask how long the cleaning method should keep the roof algae-free. A range of two to five years is normal.
As with hiring any contractor, ask family and friends for references or check online consumer reviews from a trusted source, get several bids, seek and contact references, and confirm liability and workers’ compensation insurance.