Insulating my hip ceiling
OK.. 1880 foursquare, Hip Roof, Balloon Frame construction. I hated the low ceiling height so I’m almost done building a hip ceiling directly below the hip roof.
The outside of the rafters sit on a 2×4 ledge attached with 3/8 lag screws and the ceiling frame is built with 2×6’s. I will keep (god I wish I didn’t have to) or replace the old ceiling joists with 2×6 exposed beams to provide tension and keep the house from opening up with any snow load.
We just experienced a tornado system that ripped siding off and destroyed my window trim and the house was fine. I have a ton of 3″ EPS Blue Dow R-15 16″ wide foam and I was thinking of using that as a base for insulation either on top or between the rafters/joists along with fiberglass or rock wool.
There will be plenty of room for ventilation and I am installing a whole house fan at the top of the stairs (about where camera angle is from). The ceiling rafters if you will…are about 16 on center.
My question is: should I install it between the joists and rock wool over the top or install and tape it and install rock wool between the joists? I could load it with blow in but I’m afraid that won’t be good with the whole-house fan. Any thoughts? And thanks.
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