Minidoka County, ID Insulation Payback
Minidoka County attic insulation, by the numbers
Minidoka County, Idaho is zone 5 under DOE's climate map (Cold), which means a real winter that drives most of the annual energy bill here. An uninsulated attic there should be built up to R-60. For an attic around 1,000 square feet, closing the gap from R-2 to R-60 costs around $3,480 and saves an estimated $1,820 a year — payback in roughly 1.9 years. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,733 a year on the heating side, $87 on cooling. By estimated insulation savings, Minidoka County lands in the 73th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Minidoka County comes in 264th by savings. Idaho averages $1,995/year across the counties tracked here; Minidoka County comes in 9% lower.
The climate data behind this
NOAA's MINIDOKA DAM, ID US station, 14.3 miles from Minidoka County, supplies the 6,483 HDD and 541 CDD this estimate runs on. That combined heating-and-cooling load ranks Minidoka County 891st nationally by total degree days — the 72th percentile. One local detail the R-value alone won't tell you: Minidoka County sits in moisture regime B (dry), which can affect the vapor-barrier choice.
If the attic isn't bare
A shallower starting point changes the math: with R-11 already down, only the gap to R-49 needs filling, at roughly $2,280 for an estimated $266/year saved (~8.6-year payback). Call this borderline rather than a clear win.
Quotes and materials for this job
Actual quotes will vary by attic access, existing debris, and whether the job needs air sealing first. Treat the $3,480 figure above as a planning number for Minidoka County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Minidoka 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.