Insulating a Rim Joist With No Mudsill
So hopefully I’m learning from what I’m reading here or may be clueless. I want to insulate a rim joist in an old house that has no capillary break or mudsill. The joists sit directly on the stone wall on the west and east side of the house. The front of the house you can’t access the rim joist all I see is a concrete ceiling. I think it was a converted front porch. The back side of the house has joists embedded in concrete. The rim joist all around except for the front of the house is above grade. I guess my questions would be:
1. On the east and west side of house can I put 2in eps directly against rim joist with 1in rigid board mineral wool over that for a fire barrier. The top where mudsill would be I leave uninsulated.
2. I have some plumbing that is extremely close to the rim joist in 1 or 2 cavities. Could I just leave those uninsulated so I can see the pipes at all times and I don’t freeze them behind insulation?
3. On wall that has embedded joist, I want to just leave it be and not deal with any potential problems. Yes there would be heat loss but I’m insulating other areas of the rim joist.
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