I currently live in MN and have a older 1 1/2 story remodeled farm house. The upstairs has knee walls in about 8 ft from the side and stand about 4 ft inside from there to just about the peak of the roof it is 2x4 with 3 1/2" of fiberglass insulation. My roof seldom has snow (lots of propane).
I need to reroof and I have been considering tearing off the shingles and laying a layer of 2" high density foam over the existing plywood with a new layer of 1/2 plywood on top of that and then new shingles.
My question is has nayone done this and are the results worth the effort?