Davison County, SD Insulation Payback
Davison County attic insulation, by the numbers
Davison County, South Dakota 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. 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 $2,055 a year — payback in roughly 1.7 years. Topping up the attic pays for itself fast here.
Heating vs. cooling in Davison County
Split it out and it's roughly $1,904 a year on the heating side, $151 on cooling. By estimated insulation savings, Davison County lands in the 85th percentile nationally. Zone 6 alone covers 459 counties in this dataset, and Davison County comes in 343rd by savings. South Dakota averages $2,162/year across the counties tracked here; Davison County comes in 5% lower.
Davison County's actual weather, not a national average
NOAA's MITCHELL, SD US station, 7.2 miles from Davison County, supplies the 7,122 HDD and 940 CDD this estimate runs on. Combined heating and cooling load puts Davison County in the 86th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Davison County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
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 $300/year saved (~7.6-year payback). Worth doing on the numbers alone.
Getting it done in Davison County
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 Davison County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Davison 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.