Been told that to insulate between the joists under a metal roof, the metal must first be covered with foam either sprayed on or in sheets and then fiberglass insulation under that. Another person told me that there must be minimum one inch air space between metal and fiberglass and no foam. What is proper method for doing this? Joists are 2x6 with 1x6 furring strips a foot apart and metal screwed to furring strips. Soffits and peak well ventilated.
Bob