Benewah County, ID Insulation Payback
Benewah County attic insulation, by the numbers
DOE classifies Benewah County as climate zone 5, cold — winters that dominate the energy bill, with cooling a minor factor. Its recommended attic R-value for bare joists is R-60. Topping up a typical 1,000-square-foot attic from bare joists (R-2) to R-60 runs an estimated $3,480, and saves about $1,805 a year in heating and cooling — a payback around 1.9 years. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,752 a year on the heating side, $53 on cooling. By estimated insulation savings, Benewah County lands in the 73th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Benewah County comes in 282nd by savings. Idaho averages $1,995/year across the counties tracked here; Benewah County comes in 10% lower.
Where these numbers come from
Benewah County's climate figures — 6,553 heating and 331 cooling degree days a year — are read from SAINT MARIES, ID US, 7.2 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Benewah County in the 69th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Benewah County sits in moisture regime B (dry), which can affect the vapor-barrier choice.
Already have some insulation?
If Benewah County's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-49. That smaller top-up costs around $2,280 and saves an estimated $263/year — payback about 8.7 years. Call this borderline rather than a clear win.
Next steps for a Benewah County attic
Real bids depend on how easy the attic is to reach and whether old insulation needs removing first, so treat $3,480 as a starting estimate for a Benewah County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Benewah County's R-60 target and its degree-day figures both come from named federal sources - see the methodology guide for exactly which ones. The guide to what R-value actually means explains why R-60 is the target here specifically.