Living in the Midwest (Kansas City), in a finished basement should you insulate the whole wall? And what R-value?
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| Posted in Energy Efficiency and Durability on
8 foot basement walls with 16″ above grade.
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How is this basement finished and what kind and location of insulation where you considering? Interior cavity insulation? Exterior foam board?
You're in the northern end of climate zone 4, in which the minimum recommended insulation is R-10 foundations (below grade) and R-13 walls (above grade).
Is the basement dry? If not, then full exterior insulation, waterproofing and drainage may be a sensible option.
Chris,
Assuming the house is already built, it will be easier to insulate your basement walls from the interior than the exterior. Although the code calls for a minimum of R-10 insulation, thicker insulation will give you better performance.
I recommend that you install at least R-10 rigid foam insulation on your walls. Another option is to use closed-cell spray polyurethane foam.
Don't forget the rim joist area, which needs to be carefully air sealed and insulated. The best product for the job is definitely two-component spray polyurethane foam.