Mr RB
Well-Known Member
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AND try to find some cost effective coating that will work on asphault shingles.
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We painted the top of our sunny side awning with a roller and cheap white gloss acrylic paint. It's waterproof (when dry!) and extremely reflective, and a few years later has held up very well.
Acrylic can be difficult to use on some absorbent surfaces because it just soaks in instead of coating so you need a primer. Our awning was fibreglass so it coated perfectly. It would be easy enough to test on one shingle to see if will work. The difference in heating between a gloss white roof and and a black asphalt roof would be enormous.