Insulating a Cathedral Ceiling

Find out why insulating a cathedral ceiling requires you to either add a sandwich roof structure or a scissor truss, both of which change the shape of your home. Your other option, which is still work-intensive, is to cover the underside of the ceiling with isocyanurate foam boards and then drywall over it. However, your main concern should be preventing condensation by leaving enough space for air to move above your insulation.