Comp or wood shingle? Here I see that happening with shakes and wood shingle but not with comp. Here, it seems to work for 3 -4 feet and then peters out on a comp roof but will keep the roof clear to the eaves on shakes and wood shingles. I think it's got to do with absorbency; the wood cover absorbs the stuff leaching off the copper or zinc but the comp doesn't - at least not what I've been seeing here. I suppose there can be different varieties of mosses and alga that are adapted to various regions that react differently. If there are, I can't imagine what it takes for a roofing manufacturer to reach an acceptable balance. Still convinced the stuff does damage roof covers. Bill, for the record, I hate roof cleaning companies. If I were King of the Planet, the state would issue home inspectors seasonal hunting licenses and allow them to thin out the roof cleaner herd once a year. Every inspector would have a 2-kill limit. Inspectors would be lauded as heroes for doing a service to humanity. [:-devil] ONE TEAM - ONE FIGHT!!! Mike Bill; I don't understand your hate for roof cleaners. What has any roof cleaner ever done to you for you to make the totally assinine and truly non-professional remarks that you made in this post. What puts home inspectors so far above roof cleaners that you think they should be granted the power and authority to "thin out the roof cleaning herd"? Is this just "ones man's biased opinion, or do you really have some kind of bone to pick with the roof cleaning industry?" Your comments could almost fall under "terroristic threatning" under the new laws. Perhaps you should give more "professional" thought to your comments before you make them. I really would like to know your "beef' with roof cleaners. Care to explain?
