Hamilton County, IN Insulation Payback
Hamilton County attic insulation, by the numbers
Hamilton County, Indiana is zone 5 under DOE's climate map (Cold), which means a real winter that drives most of the annual energy bill here. An uninsulated attic there should be built up to R-60. Topping up a typical 1,000-square-foot attic from bare joists (R-2) to R-60 runs an estimated $3,480, and saves about $1,687 a year in heating and cooling — a payback around 2.1 years. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,540 a year on the heating side, $148 on cooling. By estimated insulation savings, Hamilton County lands in the 65th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Hamilton County comes in 505th by savings. Indiana averages $1,634/year across the counties tracked here; Hamilton County comes in 3% higher.
Hamilton County's actual weather, not a national average
Hamilton County's climate figures — 5,758 heating and 920 cooling degree days a year — are read from CARMEL 3 E, IN US, 6.6 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Hamilton County in the 65th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Hamilton County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $246/year saved — roughly 9.3 years to break even. Call this borderline rather than a clear win.
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 Hamilton County's estimated $1,687/year on the line.
Where these figures come from
Hamilton 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.