Vented Cathedral Ceiling — Affordable Insulation
About a year ago, when i moved in to our new (old) home in Montreal. I had an energy audit done that really highlighted the piss poor job of insulation the previous owners had done with their attic conversion.
So, hence, we am in the process of re-doing the insulation in my cottage style 75 year old 1.5 story cathedral roofed home. There are rafters that are 2×5, that would need to be “furred” out. Also, when I moved in, we re did the old roofing shingles, installed a ridge vent, and am in the process of drilling 1″ holes in the blocking on the bottom of rafter the opens venting above the soffits.
There was previously (from sheathing down) air baffles (without venting… figure that) and about 4 inches or fiberglass, then a poly sheet, and sheetrock.
I would like, and find that the following insulation solution, would fit my budget and hopefully also my insulation needs. I have approximately 1000 sq ft of roofing.
1″ home made air venting made from 1/4″ OSB with caulking to seal gaps.
5.5″ Roxul R22
1″ Extruded Polystyrene over lapping rafters for thermal bridge @ R5
Can I please get some feedback from some more experienced builder out there?
How does the plan sound… sound? what about the placement of the poly, should it be above or below the polystyrene? Am i missing something?
I appreciate the help.
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