Insulating rim joist between floors
I am insulating my 3rd floor attic that contains my HVAC system and ductwork. It will be done with ccSPF, rockwool, and Bonfiglionli like furring. The attic is currently conditioned, but not insulated. The floor currently has R30 fiberglass in it.
My immediate question is should I cut back the floor as have them spray foam the rim joist between the 2nd and third floor? Is it doable and worth the effort?
Cutting the floor on the front and back of the house takes where the joists/rafters end would take some work, but pretty straight forward. I am not sure how to do the gable ends though as the walls sit on the flooring and the outside most joist. There wouldn’t be anything to screw the floor back down to. I could possible install a new joist just inside the wall, leaving enough room for insulation.
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