Wall cavity insulation
I live in climate zone 7 (Canadian prairie).
I’ve been doing some demo work on the inside of my old story and a half house (1940ish). No eave extension, no soffits.
I see there’s no insulation on the main floor – just some wood chips settled at the bottom of the stud bays and some silver/black/silver paper and thick cardboard type sheet stapled across the wall, topped with plasterboard.
The house exterior is original stucco. I can’t tell if the stucco has felt under it. Based on the areas of stucco that are chipped, I don’t see any evidence of felt. The house has multiple air leaks and the flashing above the new windows is old.
I’d like to add insulation to the stud bays. My approach would be to add roxul then poly, then drywall. I am concerned that moisture would still be allowed to travel through the stucco and sit in the stud bay leaving it damp and the house not smelling so good.
Couple of questions:
If I choose to leave the stucco as is – how should I finish the inside in terms of insulation, poly/no poly, etc?
I understand there’s some kind of flashing detail called dam flashing (?) where the flashing curves up at the ends and prevents water from dripping down the sides of windows. I’m wondering if that can be installed after the fact – perhaps as an add full length strip under the original flashing?
Exterior details such as slight cracks between the stucco and the windows, stucco and chimney, should be sealed with some kind of exterior caulk, correct?
And lastly, ripping off the stucco down to the sheathing would be a big expensive job. Would reassembly be: something like house wrap, rainscreen gap, then stucco or fiber cement siding? Do the windows stay in place during this process or do they need to be removed to have the house wrap done? And then interior wall assembly could be the regular old school batt insulation, poly, drywall.
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