Embedded floor joists air sealing
I have a 1960’s bungalow in Canada where the 2×10 floor joists have been embedded/cast into the concrete foundation wall. The foundation wall stops about 1″ below the floor sheathing.
I have been considering insulating the rim joist area but because of the embedded joists I don’t feel this is a very good idea because of the potential for the joist ends to rot in winter. It seems the best option is to leave that area un insulated.
What I am wondering is if there is any concerns with just air sealing it? I would do so by filling the 1″ gap at the top with spray foam and then caulking around each joist. would preventing air movement to these embedded portions of the joist also potentially cause moisture to build and rot to form?
P.S. Insulating on the exterior with foam is not an option at this time.
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