If you have seen some of my old threads you know that we are building our house. Most of the lumber came from my trees. I have a buddy with a sawmill so he cut all the framing and subfloor upstairs.
Well, we mostly finished electrical and plumbing rough in so I had the metal roof put on and the spray foam done.
For the metal roof, we went with galvalume r panel. I bought a bunch of used blue XPS. I had them put 2x4s horizontally spaced 4' apart. Then they put in two layers of the 3/4" foam sheets between the 2x4s. This gives me R7.5 above the roof deck.
For the spray foam, I paid for 3" of open cell foam but got 4" in most of the house. In some places, I got 5.5" (fill the cavity). Assuming 3.5", I have R13 in the walls and attic rafters. That puts me at R20.5 in the attic and right now have R13 in the walls.
The walls will get two layers of rigid on the outside as well. So, the whole house will be at least R20.5. For east texas, that is pretty good.
Austin
