Breaking thermal bridge between concrete porch and brick wall?
I have a concrete-floor porch that replaced an original wood-floor porch. It butts up right against the double-brick wall of the house (built in 1905). The house is uninsulated, so I am insulating the brick wall with rigid foam board. While I’m at it, I am thinking it is a good idea to saw-cut a 1″ or 2″ slot of the concrete floor right along the base of the brick wall (in other words, the floor-wall joint) to get rid of the thermal bridge that might exist, then to backfill the slot with rigid foam. Does this sound like it would make a significant difference to heat conductivity? I’m in Toronto. Thanks.