I realize that multiple posts and answers may have already been posted, but here goes my question. I just recently transformed a 10′ x 20′ screened porch into a 3 season room. This room was built off a split entry, which now has a “basement” of a poured slab and cider block foundation with 2″x6″ studded walls, underneath the 3 season. Because the basement has various yard equipment, I am going to insulate the floor of the 3 season with CC foam, to make the possibilty of any exhaust from the snow blowers, and yard tractors unable to enter into the above living space. The big question I have is does it make sense to use the spray foam for the roof of the 3 season (2″x6″ construction) without venting? I do not have a ridge vent on this addition and the only way to vent it economically would be to possibly install a gable vent (my bad, the roof was reshingled as a screened porch and I didn’t make venting a priority). The electrical rough in has been completed and before drywalling I really need some advice. Any thoughts or comments would be greatly appreciated.