Chouteau County, MT Insulation Payback
Chouteau County attic insulation, by the numbers
DOE classifies Chouteau County as climate zone 6, 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 $2,136 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 $2,070 a year on the heating side, $66 on cooling. By estimated insulation savings, Chouteau County lands in the 88th percentile nationally. Zone 6 alone covers 459 counties in this dataset, and Chouteau County comes in 254th by savings. Montana averages $2,182/year across the counties tracked here; Chouteau County comes in 2% lower.
Chouteau County's actual weather, not a national average
Chouteau County's climate figures — 7,741 heating and 413 cooling degree days a year — are read from LOMA, MT US, 4.6 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Chouteau County in the 88th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Chouteau 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 $312/year saved (~7.3-year payback). Worth doing on the numbers alone.
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 Chouteau County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Chouteau 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.