Gut remodel insulation?
KMartin6
| Posted in GBA Pro Help on
We’re gutting a kitchen and dining area, and are trying to figure out what insulation to use.
Wall construction is 2×4 stud with stucco exterior, interior will be sheetrock. House is in Northern Illinois.
Whats the best insulation to put in before drywall? We’ve looked at fiberglass batts (tricky as the studs are quite irregular in spacing) cutting 2″ foam sheets and taping/foaming into place, and spray foam kits.
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Replies
Kris,
Before you can decide how to insulate, you need to assess the stucco installation details. Does your house have sheathing (boards or plywood) or no sheathing? Can you tell if there is any asphalt felt between the sheathing (if any) and the stucco? (I'm assuming there is no air gap between the stucco and the felt -- that's unlikely.)
Thanks for the quick reply and in the insight.
There is 3/4 board sheathing, and oddly, felt as some places and not others. I believe at some point the exterior stucco was partially redone, although I'm not sure if there areas with sheating at the redone areas or not.
Additionally, there is an old enclosed porch which has the variety pack: one wall has plywood sheating under paper, another wall has just lathe then stucco behind the studs, and the other has board sheathing.
So, I'm answering your either/or questions with a yes!
Thank you
Kris,
Now that we know your conditions... I'm hoping that an insulation contractor with a lot of experience with stucco will chime in.
If it was my house, I'd be inclined to strip off the stucco and switch to another form of siding, if I could afford it. Stucco is the most problematic of all siding types for wood-framed buildings. It's possible that the only reason that your wall has avoided moisture problems for all these years is that you have empty stud cavities that dry quickly.
You need a good layer of sheathing, a good WRB like asphalt felt or housewrap, and good window and door flashing. Then (ideally) you need a ventilated air gap, and then the siding of your choice.
Without those things -- if you just fill your stud bays with cellulose or spray foam -- it's hard to predict what will happen around your windows after a year of rain.