Questions on rim joist and poured wall insulation
I’m insulating a room in my basement to store wine. This will not have any temp or humidity control in it, I just want to minimize the temperature fluctuations throat the year. It’s gotten too cold in the winter and too warm in the summer (zone 6a). The first two areas are the rim joists and the pound walls.
I removed the builder installed (1999) leftover wall fiberglass stuffed in the rim joist. I cut 1.5″ XPS to loosely fit, glued it on, and spray foamed the gaps.
1. Should I add one more layer of 1.5″ and gap fill before a unfaced top layer?
2. Would either mineral wool or fiberglass be better for the top layer and would 3.5″ be appropriate?
I’ve added one layer of 1.5″ XPS to the poured walls and am spray foaming the perimeter. The walls are pretty irregular and there are gaps behind the XPS.
3. Is my assumption that gaps behind the insulation are fine as long as they are sealed in with the XPS and spray foam?
4. Will building a 2×4 wall in front of the foam and insulating with unfaced mineral wool or fiberglass be a good approach?
5. is there any issue with using horizontal boards (no vapor barrier) on the face of the wall present any problems?
Thanks for any advice,
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