"3. Add insulation beneath the roof. 1" or thicker foam sheet (maybe PolyIso foam with the foil layer facing up) beneath the roof should help block the heat radiating downward."
That would work for sure. But, an air-gap sandwiched in there would help out..
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My PV assisted hot water isn't working so well these days. The sun is so high during
the best part of the day, with the tree tops hanging out so far, I get shade just after noon time..
Need to oil up the saws!!