I’m considering having my attic, crawl space, and rim joists insulated with spray foam to make my house more comfortable. The house has two attics with a slanted cathedral ceiling between them. One of the attics butts up against an additional slanted cathedral ceiling. My understanding is spray foam will seal the attics and no longer allow them to breath. Will I have a problem if I spray the open attic spaces but leave the cathedral ceilings insulated with fiberglass? Thanks!