Can I use spray foam insulation on attic trusses on an ICF home?
I am building an ICF home using Reward walls, footings to rafter, with no sill plate, but using hurricane straps. Walls are 13" with 2.5' on each side for insulation and 8" of concrete fills the cavity.
I have attic trusses and am unsure how to best insulate this without having moisture problems with this tight of a home. It looks like I can use a minimum of 2 inches of spray foam and then fill the rafter top cords with batt insulation. Does the entire rafter cavity need to be filled? The trusses are varing lengths with the open living space just under 14 total feet.
Do I insulate the side walls if I insulate the entire rafter? I also have one area that overhangs 5 feet. Does this pose any additional concerns if I do not vent this area? Looking for advice.
Posted Nov 20, 2012 10:37 PM ET
Edited Nov 21, 2012 6:22 AM ET
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