Powder River County, MT Insulation Payback
Powder River County attic insulation, by the numbers
Powder River County sits in IECC climate zone 6 (Cold) — a real winter that drives most of the annual energy bill here. For a currently uninsulated attic, DOE and ENERGY STAR recommend building 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 $1,962 a year — payback in roughly 1.8 years. Topping up the attic pays for itself fast here.
Heating vs. cooling in Powder River County
Split it out and it's roughly $1,837 a year on the heating side, $125 on cooling. By estimated insulation savings, Powder River County lands in the 80th percentile nationally. Zone 6 alone covers 459 counties in this dataset, and Powder River County comes in 419th by savings. Montana averages $2,182/year across the counties tracked here; Powder River County comes in 10% lower.
Powder River County's actual weather, not a national average
NOAA's BROADUS, MT US station, 7.6 miles from Powder River County, supplies the 6,871 HDD and 779 CDD this estimate runs on. Combined heating and cooling load puts Powder River County in the 81th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Powder River County sits in moisture regime B (dry), which can affect the vapor-barrier choice.
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 $286/year saved (~8-year payback). Worth doing on the numbers alone.
Quotes and materials for this job
Get more than one quote before committing. Attic access and any needed air sealing move the price around, and most contractors won't take a job below roughly $600 regardless of size - worth asking upfront given Powder River County's estimated $1,962/year on the line.
Where these figures come from
Powder River 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.