Basement Wall Insulation
I am soliciting quotes from contractors to waterproof (not damp-proof) my poured concrete basement walls. I have asked the bidders to include installing 4″ of XPS (R20) after completing the waterproofing and before backfilling the trench. Estimates so far are coming in higher than I anticipated.
As I look to finish the basement interior I am also thinking of insulating the interior (to provide the necessary vapor retarder) with the thought of reducing the amount of exterior insulation I have the contractor install with the waterproofing project. So my question is….is the insulation that is installed on the exterior and the interior have a cumulative effect or is there a reduction in effectiveness due to the highly conductive nature of the concrete?
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Replies
Pete, next time you get an estimate get it from a contractor who would actually perform the work. Then the estimate comes in the same.
Insulate just the interior to get your best price and highest R. Rigid plus PT framing plus batts plus paperless drywall or use OC cellar wall panels.
Insulation is additive, so your interior + exterior approach would work.
David thanks for answering my rather simple question. I figured I risked some friendly jabs with a question like this.