Elmore County, ID Insulation Payback
Elmore County, ID: what topping up your attic actually costs
DOE classifies Elmore County as climate zone 5, cold — cold enough that heating, not cooling, is what decides the bill. 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 $2,305 a year in heating and cooling — a payback around 1.5 years.
That's about as fast as attic paybacks get.
Where the savings come from
The estimated savings split roughly $2,276/year heating, $29/year cooling. Out of every 100 US counties tracked here, Elmore County's savings potential beats roughly 93 of them. Within zone 5 specifically, it ranks 3rd of 754 counties by estimated savings. Idaho averages $1,995/year across the counties tracked here; Elmore County comes in 16% higher.
The climate data behind this
Elmore County's climate figures — 8,513 heating and 182 cooling degree days a year — are read from Hill City 1 W, ID US, 21 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Elmore County in the 93rd percentile of this 3,171-county dataset. Elmore County falls in DOE's moisture regime B (dry), a detail that affects vapor-barrier recommendations more than the R-value target itself.
Already have some insulation?
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $336/year saved — roughly 6.8 years to break even. That is a solid payback as home upgrades go.
Getting it done in Elmore County
Get quotes from at least two local contractors 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 checking upfront given Elmore County's estimated $2,305/year on the line.
Nothing here is a guess
Every figure on this page traces to DOE/IECC climate zones and NOAA degree-day normals, documented in the methodology guide. The guide to what R-value actually means explains why R-60 is the target here specifically.