Brick & mortar inside of rim joist
After my energy audit I was told to insulate the rim joist of my 1921 old brick exterior house. I started researching and found that insulating against brick was bad because of the inability for moisture to move through the brick effectively. Luckily through digging deeper into my house I found it was stick built with the brick on the outside. But when I went downstairs to look at how to insulate the rim joist I saw the floor joists going into brick. This confused me. It also led me to Green Building Advisor where I found more information about insulating against brick was a bad idea but all that information was because the brick was exterior or foundation related. I walked the whole interior and found out that there is a wood rim joist and they put brick and mortar inside of that wood rim joist.
My question is…
Does the same theory about insulating against brick apply if it is inside the rim joist as if it was an outside foundation brick?
Joist are above grade. Brick exterior all the way to the ground, exterior insulation is not an option. Climate zone 6b
I would like to caulk, foam board, and spray foam if possible.
If doing all that will cause a moisture issue, is caulking all the seems my only option?
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