Rigid Insulation on the interior walls during remodel

KHM

I'm in Montana and currently remodeling kitchen, dining, living room. We are going to be down to the studs (pulled off 70's era glued paneling, sheet rock pretty torn up). The original batt insulation was not well installed so we are going to pull the batts back, hand foam the joints where the sheathing and 2x6 studs meet and then replace the batts properly. There's a a lot of window surface (which we love) but it means lots of studs and doubled, tripled studs. A friend recommended putting and inch of rigid insulation on after replacing the batts, to create a thermal barrier, then put on new sheetrock. I realize this is reverse of how rigid insulation is usually installed (from the outside) but will this work?
Montana is a VERY dry climate and a very cold climate so things like mold and termites are not a big concern.

OR... with the sheetrock off and the batts out, should I go for one of those dyi spray foam kits?

Very intersted to hear some thoughts on this.

the carpenter

I've seen the rigid insulation on the inside before and I think its a great idea. Expensive but great. foilback is supposedly the best. With Tuck taped joints, this will be an excellent vapour barrier as well as being a thermal break for the studs.

As far as it usually being installed on the exterior of the house, that kinds of scares me. Isn't the styrofoam creating a waterproof barrier? I've seen guys putting foilback styrofoam insulation on the outside of houses, taping every joint and then slapping a high five for a "tight house". It would seem to me that they are creating a situation where a house cannot breathe. If moisture ever gets in, hows it going to get out?

Type of styrofoam may be an issue. You may want to research what types are breathable and what types are acceptable for a vapour barrier.

Gary in WA

Here's some info to get you started:

http://www.buildingscience.com/docum...gs?full_view=1

And insulation ratings: http://hes.lbl.gov/hes/makingithappe...omparison.html Be safe, G