Need advice on insulating basement walls that already have framing
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| Posted in General Questions on
Purchased a new but unfinished home. Basement has been completely framed but there is no insulation. Taking down the framing on the outside walls is going to be next to impossible. Also prefer not to spray foam for various reason.
I understand batts are not a good idea due to condensation that can occur on the cold concrete wall. Can I put rigid foam on the walls instead between the studs? How about using fan fold foam (there is 1/4″ or so space between the studs and the basement concrete walls) and then batts over that?
Any other ideas?
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Replies
Patrick,
The best approach is to remove the studs. Stud walls are fairly easy to demolish. It's even possible to do the demolition in a way that will allow you to salvage most of the material.
Get a circular saw and a reciprical saw and just start working. You'll be surprised how much you can demolish in just two hours.
Once the demolition is done, you can insulate the walls properly. Here's an article that tells you everything you need to know: How to Insulate a Basement Wall.
Thank you for the reply Martin. I agree, removing the studs is the ideal way to do it. I should have added that the basement is completely wired through all of the studs as well. So that adds to the complexity and cost. So am still hoping for an alternative method.
Patrick,
If you really want to avoid demolition, then I advise you to hire a spray-foam contractor. Make sure that the contractor begins by spraying the (tiny) space between the backs of the studs and the concrete.
If you don't like spray foam... hire an electrician to dismantle the wiring.
What Martin said, but I'd add:
Only closed cell spray foam is sufficiently moisture-proof enough to protect the stud edges from the concrete, and it's not all that green at higher R. A 1" shot of closed cell for moisture control, and carefully installed unfaced R13s (assuming 2x4) tucked and fluffed at the edges for complete cavity fill, split over the wiring & plumbing and trimmed to fit snugly around electrical boxes works. An R13 compressed into a 2.5" nominal space still delivers R10 performance on it's own, (see: http://www.owenscorning.com/literature/pdfs/10017857%20Building%20Insul%20Compressed%20R-Value%20Chart%20Tech%20Bulletin.pdf ), plus the R6-ish for the inch of closed cell foam makes it comparable in R-value to using high-density R15 fiberglass or rock wool batts, but more air-tight and with better moisture control.