question:i have a shingle roof on 90 % of house.
but i noticed blk area's forming like looking like a fire.
burnt looking area's how can i clean this up ?
bleach/brush etc.
Around roof vents it could be heat damaged shingles from hot air coming out of the (usually undersized) vents.
If it is all around the roof, it is likely mold or mildew or algae which can be scrubbed off with a bleach/water solution or other cleaners available from roof suppliers.
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