Adair County, IA Insulation Payback
Adair County attic insulation, by the numbers
DOE classifies Adair County as climate zone 5, cold — a real winter that drives most of the annual energy bill here. Its recommended attic R-value for bare joists is 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 $1,912/year saved. Topping up the attic pays for itself fast here.
The breakdown behind the number
Split it out and it's roughly $1,772 a year on the heating side, $139 on cooling. By estimated insulation savings, Adair County lands in the 78th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Adair County comes in 133rd by savings. Iowa averages $1,985/year across the counties tracked here; Adair County comes in 4% lower.
The climate data behind this
The heating and cooling degree days behind this estimate — 6,628 HDD and 868 CDD (base 65°F, 1991-2020 normals) — come from GREENFIELD, IA US, the nearest NOAA station with published normals, 2.9 miles from Adair County's center. Combined heating and cooling load puts Adair County in the 79th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Adair County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Adair 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 $279/year — payback about 8.2 years. Call this borderline rather than a clear win.
Next steps for a Adair County attic
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 Adair County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Adair 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.