Power County, ID Insulation Payback
Is attic insulation worth it in Power County, ID?
Power 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. 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 $1,838 a year in heating and cooling — a payback around 1.9 years. Few home upgrades pay back that quickly.
Heating vs. cooling in Power County
Heating accounts for about $1,740/year of that and cooling about $98/year — Power County needs both. Nationally, Power County ranks in the 75th percentile for insulation savings potential. Compared only against its own climate zone, Power County places 225th out of 745. Against Idaho's own average of $1,995/year, Power County runs 8% below that.
Power County's actual weather, not a national average
Power County's climate figures — 6,507 heating and 608 cooling degree days a year — are read from AMERICAN FALLS, ID US, 7.5 miles away, NOAA's nearest 1991-2020 normals station. That combined heating-and-cooling load ranks Power County 833rd nationally by total degree days — the 74th percentile. Its moisture regime is classified dry, which matters for whether the attic needs a vapor retarder as part of the job — worth asking a contractor about locally.
The smaller top-up scenario
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 $268/year saved (~8.5-year payback). Whether that is worth it depends on how long you plan to stay.
Next steps for a Power 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 Power County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Power County's numbers, sourced
The methodology guide lists exactly which DOE and NOAA sources feed Power County's numbers, and where the cost assumptions come from. See the DIY vs. contractor guide for whether a job this size is realistic to do yourself.