Doniphan County, KS Insulation Payback
Doniphan County, KS: what topping up your attic actually costs
Doniphan County, Kansas is zone 4 under DOE's climate map (Mixed-Humid), which means heating load in winter and cooling load in summer, both worth taking seriously here. 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 2.1 years at an estimated $1,661/year saved. That's about as fast as attic paybacks get.
The breakdown behind the number
The estimated savings split roughly $1,469/year heating, $193/year cooling. Out of every 100 US counties tracked here, Doniphan County's savings potential beats roughly 63 of them. Within zone 4 specifically, it ranks 13th of 825 counties by estimated savings. Kansas averages $1,594/year across the counties tracked here; Doniphan County comes in 4% higher.
Where these numbers come from
NOAA's TROY 3N, KS US station, 4.2 miles from Doniphan County, supplies the 5,493 HDD and 1,200 CDD this estimate runs on. That combined heating-and-cooling load ranks Doniphan County 1087th nationally by total degree days — the 66th percentile. Doniphan County falls in DOE's moisture regime A (humid), a detail that affects vapor-barrier recommendations more than the R-value target itself.
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 $242/year saved (~9.4-year payback). 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 Doniphan County's estimated $1,661/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.