I am working on a house plan right now with brick veneer exterior walls w/ 2x4 studs. I typically just draw in 1/2" or 5/8" gypsum on the inside, studs, 1/2" sheating ply., 1" air gap, and then the brick veneer. The builder asked me to change the 1/2" sheating ply. to 1 1/2" rigid foam insulation. I haven't drawn a house with this and I dont really know much about it. Can I just replace the 1/2" sheating with the 1 1/2" rigid insulation, or does it nail to the sheating? Any type of information and help about rigid insulation would be greatly appreciated. Thanks.
-Rainer
-Rainer