rigid or sprayed in closed cell insulation?
We’re still trying to figure out what would be the best approach for insulating the dormer section of the roof (with 2×6 rafters). Once we get the proper vents in the correct place, would it be best to use 2 or 4 inch rigid insulation or have an insulating company come in and spray the closed cell foam? Do we need proper vents if we go with the 4 inch rigid? There would be a 2 inch gap behind it. I haven’t done enough research on the closed cell sprayed in foam to understand how that is applied in a ceiling.
Thanks,
haw1