Natrona County, WY Insulation Payback
Natrona County attic insulation, by the numbers
Natrona County, Wyoming is zone 6 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 $2,159 a year in heating and cooling — a payback around 1.6 years. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $2,093 a year on the heating side, $66 on cooling. By estimated insulation savings, Natrona County lands in the 89th percentile nationally. Zone 6 alone covers 459 counties in this dataset, and Natrona County comes in 234th by savings. Wyoming averages $2,161/year across the counties tracked here; Natrona County comes in 0% higher.
Natrona County's actual weather, not a national average
The heating and cooling degree days behind this estimate — 7,827 HDD and 411 CDD (base 65°F, 1991-2020 normals) — come from POWDER RIVER #2, WY US, the nearest NOAA station with published normals, 11.8 miles from Natrona County's center. By total degree days, Natrona County sits at the 88th percentile nationally. One local detail the R-value alone won't tell you: Natrona County sits in moisture regime B (dry), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Natrona 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 $315/year — payback about 7.2 years. Worth doing on the numbers alone.
Getting it done in Natrona County
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 Natrona County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Natrona 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.