Truthfully, a bit hotter because there's no breeze. But we could certainly cut windows, cover them with hardware cloth and put awnings. We have lots of left over siding from our garage.
Get the cool air moving in and the hot air moving out and it should be OK then. Use a thermometer to double-check -- heat is a severe problem when you wear a down parka year-round.
Would insulation in the roof help?
Not as much as airflow moving under the roof would.
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