I saw a truck yesterday with advertizing stating 'Powerwashing of Roofs' and couldn't stop laughing. These guys are incredible. Many people get stains and fungi on roofs, and yes it is unsightly, but a good roofing contractor will never powerwash a roof.

Roofing shingles have a granular surface that slowly washes off with the rain, as it should. But to accelerate this process is asking your roof to expire early.

Some things were not meant to be powerwashed, and your roof, no matter how much fungi it has growing on it, is one of them. Use a putty knife to remove the heavy stuff, and then use a soft brush with some Clorox diluted in water to remove the rest, or better yet, call a professional. -Ray