I'm finishing my basement in southeastern Wisconsin. This is a poured full basement below grade. We are ready to insulate the walls and are going to use closed cell spray foam.
I've had two different contractors come out and recommend different thicknesses for the foam. One said I only need 1" against the walls, and 3" in the sills. The other said 2" against the walls and 3" in the sills.
What kind of performance gain would I be looking at between 1" and 2" sprayfoam?