Insulation/fan
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Perhaps I’m overthinking this. In Minneapolis, climate zone 6A…….painted cedar siding, felt paper, 1×8 (plank board) sheathing, with balsam wool insulation in the walls.
Spurged for a Panasonic fan…….opening (cutout) for cylinder that protrudes through the sheathing is 9”, a lot larger cut out than the dinky little ones I have put in the past.
Anyways this got me thinking…with all the moisture drive and around the fan, with it pulling of course towards a exterior wall, and considering I have a 1′ radius around the fan exposed and able to insulate with any type of material I chose……What would be the ideal…scenario…..
I was thinking unfaced FG and then 1” XPS to the interior. I was planning on using canned foam to insulate the metal cylinder coming through the wall vs pipe insulation with the sleeve……. basically 2 options are FG with XPS interior to that or straight FG Suggestions?
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Replies
M.S.,
1. Yes, you are overthinking this.
2. I vote for canned spray foam.
3. Whatever you do, air tightness matters more than insulation type.