Oneida County, ID Insulation Payback
Oneida County, ID: what topping up your attic actually costs
Oneida County, Idaho is zone 6 under DOE's climate map (Cold), which means cold enough that heating, not cooling, is what decides the bill. An uninsulated attic there should be built up to R-60. Going from R-2 to the recommended R-60 costs roughly $3,480 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 1.8 years at an estimated $1,954/year saved. That's about as fast as attic paybacks get.
Where the savings come from
The estimated savings split roughly $1,884/year heating, $70/year cooling. Out of every 100 US counties tracked here, Oneida County's savings potential beats roughly 80 of them. Within zone 6 specifically, it ranks 423rd of 459 counties by estimated savings. Idaho averages $1,995/year across the counties tracked here; Oneida County comes in 2% lower.
The climate data behind this
The heating and cooling degree days behind this estimate — 7,046 HDD and 435 CDD (base 65°F, 1991-2020 normals) — come from MALAD CITY, ID US, the nearest NOAA station with published normals, 12.2 miles from Oneida County's center. By total degree days, Oneida County sits at the 79th percentile nationally. Oneida County falls in DOE's moisture regime B (dry), a detail that affects vapor-barrier recommendations more than the R-value target itself.
If the attic isn't bare
If Oneida 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 $285/year — payback about 8 years. This one is a genuine toss-up, not a clear yes.
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 Oneida County's estimated $1,954/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.