garanlou

I'm not sure how cold it gets in Chicago, but up in Canada it's recommended that you go R20 for basement walls. 2" rigid should get you around R10. What I'm doing in my basement is gluing 2" rigid to the walls (with tuck tape at the seams), framing over that, and filling the gaps with Roxul. That's going to get me to around R24. 10.0.0.0.1 192.168.1.254