Hi all, I am building a log kit type home in the hill country of Tx (west of SA). This is a dry area I believe designated zone 3. This is a small (600+sqft)home. I will have one section as a great room with vaulted ceilings. I intend to ventilate that ceiling w/ 1″ air channel using foam board. I will then use fiberglass batts between the 10″ rafters and ridged foam boards (edge taped) below the rafters to air seal the ceiling then have pine T&G as the finished ceiling. I believe I have read that you need a flame resistant layer over foam board. Is that true and does the wooden T&G fill that requirement or should I put up a layer of taped drywall instead of the foam? Would foil face foam do the trick?
Thanks Rob