@GBR, would you recommend putting the rigid foam against the sheathing and then the roxul insulation? I planned on doing it the opposite way, roxul against the sheathing and then foam board. I have not mentioned it prior but the roof is a rubber in case that factors into anything. There is a 1" foam board and then its one giant sheet of rubber.
I don't plan on venting the rafters, it will take to much time and money that I don't have right now. I do plan on the Roxul R23 and a rigid foam board as I stated earlier. I will tape the foam board seams but its going to be hard to seal around the recessed lights.
I looked into spray foam and it would cost ~1500 to coat the area with 1", the foam board and roxul will cost $500. Its a no brainer...
I might get the DOW spray foam and seal under the recessed light and then add the roxul/rigid foam but thats only an R4.
Last edited by drewdin; 11-30-2012 at 08:35 AM.