I started this on the other side then thought this should be asked here. I have many homes here with asbestos roof shingles. Most are dirty and almost black from who knows what is on them. Would those be cleaned the same as terra cotta? And what about slate?
Thanks for deleting Gary. I stated that, then realized... wrong place for the guys not willing to join, hell, I not only get roof advice but computer advice too. As a matter of fact, the list is growing as far as the help I found here!
I read on here over a year ago { I think Chris posted it } Not to use isp on slate roofs it will leave a " blueish/discoloration " on the slate that will last awhile. I have cleaned a couple without isp as suggested and had no problem.
Boy I've seen alot of homes but never came across asbestos shingle on a roof. I guess its a regional thing. We have asbestos shingle siding around here though.
Do not walk asbestos, very thin and brittle, and irreplaceable when broken. Strong mix needed 40% or so from my experience. Asbestos shingles collect a lot of dirt in the cracks and become a great bedding place for ferns/plants. You may have to get a push pole to bring down some of the growth before cleaning.
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Ray Burke
Spray Wash Exterior Cleaning
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