I have the following situation. I have a raised ranch and we're having drain tiles installed. I wanted to use this time to install some additional insulation while we've got wood paneling down.
The basement has 4 feet of wall below grade and then above grade cinder blocks are moved two inches toward the exterior and start going up. Studs go against the bottom section and then above the 4 foot mark, these studs are separated 2 inches from the wall. I made some ASCII art below where the X's are the wall and floor and the S represents the stud. Note the gap between the stud and the wall near the top.
X SS X SS - Cinder block above grade wall X SS X SS XXXSS XSS - Poured basement wall XSS XSS XXXXXXXX - Floor
We have a vapor barrier (plastic sheeting) stapled directly onto the 2x4s (the exterior side). Snug in between each pair of 2x4s we have R-13 fiberglass batts.
As for my questions...
1) Would it be okay for me to put some rigid foam insulation into that gap? I figure I could take down a 2x4 and start sliding insulation against the wall.
2) If I do that, should the vapor barrier be on the exterior side of the rigid panel or the interior?
3) Upstairs we have drywall attached to 1x2s which are then attached to cinder block. This situation sucks because barely any insulation fits in that tiny gap between the cinder block and drywall. This house is in Chicago too. I'm looking at my options here.
A) Rip off all the drywall and little 1x2s and put in some real 2x4s in there w/ some batt insulation. Fix all the power outlets, window sills, etc.
B) Attach foam board insulation directly onto the drywall. Then put new drywall on that. Of course fix all the power outlets, window sills, etc.
What would you guys/gals do in this situation?