A 3200 sq. ft. brick ranch. Power 3′ ceiling fan in bedroom hallway. Three 12″ powered turbine vents on roof. Soffit vents for about 75% of her 300 lineal feet of roofline. Gable end vents of about 4 sq. ft. on three sides. The house is surrounded by tall trees that supply about 30% coverage of the roof and the ridge line runs North-South. Attic floor is R-30 fiberglass batt and R-20 cellulose blown in insulation.
It was 86 outside last summer when she wanted can lights installed in her living room ceiling. I took up a thermometer just for kicks. 132 degrees. I could feel the airflow in the attic but it wasn’t very cooling. I can’t blame the heat on lack of ventilation, or insulation, or anything else. Her house is situated to not get maximum sun. She had some shade trees. And the attic was still almost deadly.
The only thing that might have helped lower the temps were lighter shingles. Hers are black/brown.
More ventilation couldn’t hurt but there is only so much you can do I guess.
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