Decatur County, IN Insulation Payback
Decatur County attic insulation, by the numbers
Decatur County, Indiana is zone 5 under DOE's climate map (Cold), which means winters that dominate the energy bill, with cooling a minor factor. 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 2.2 years at an estimated $1,585/year saved. Topping up the attic pays for itself fast here.
Heating vs. cooling in Decatur County
Split it out and it's roughly $1,405 a year on the heating side, $180 on cooling. By estimated insulation savings, Decatur County lands in the 59th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Decatur County comes in 655th by savings. Indiana averages $1,634/year across the counties tracked here; Decatur County comes in 3% lower.
The climate data behind this
The heating and cooling degree days behind this estimate — 5,253 HDD and 1,121 CDD (base 65°F, 1991-2020 normals) — come from GREENSBURG, IN US, the nearest NOAA station with published normals, 2.9 miles from Decatur County's center. By total degree days, Decatur County sits at the 59th percentile nationally. One local detail the R-value alone won't tell you: Decatur County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Decatur 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 $231/year — payback about 9.9 years. Call this borderline rather than a clear win.
Getting it done in Decatur County
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 Decatur County's estimated $1,585/year on the line.
Where these figures come from
Decatur 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.