Complex roof cathedral insulation
I’ve been looking at all the blogs and am lost. I’m sorry if this has been answered somewhere else! I am in Austin, Texas. I have a room with a cathedral ceiling that is very poorly insulated. The roof has a ridge vent and soffits on one side, so presumably is or could be properly vented. However the other section of the house meets this room at a right angle, creating one full side of the room’s cathedral ceiling that cannot be vented because there is no soffit. My question is -how should I insulate this room? I understand that I could insulate the side with soffits with an air gap – that makes sense. The other side though I dont know what to do? Should I just remove the ridge vent and soffit vents, seal the entire room and spray foam the whole underside?
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Replies
ATX,
Q. "Should I just remove the ridge vent and soffit vents, seal the entire room and spray foam the whole underside?"
A. Yes (using closed-cell spray foam). The only alternative is to demolish the roofing and to install an adequately thick layer of rigid foam on the exterior side of the roof sheathing, followed by another layer of sheathing, roofing underlayment, and new roofing.
More information here: "How to Build an Insulated Cathedral Ceiling."