Rim Joist Insulation – GreenBuildingAdvisor

Hi,

I have a house in NJ built in the 1960s and am getting ready to finish the basement. The basement walls are made from concrete block and mortar. The double 2×6 sill plate does not appear to have a gasket between the sill and concrete. 

I think I will need to insulate the inside of rim joists to pass code inspection. I’d like to use 2”XPS and spray foam around the edges. However I am concerned that by doing so, I will eliminate the ability to dry to the inside, and will potentially trap in moisture and cause rot.

The exterior of my house is brick, and there is a ~1-2” gap between the outside of the rim joist and the inside of the brick. There does not appear to be any vapor barrier or house wrap between them.

Does this assembly allow for adequate drying to the outside, or would I be at risk for trapping moisture if I was to insulate?

Any advice would be much appreciated. I want to insulate the rim, but not at the cost of long term durability. Thanks!