Spencer County, IN Insulation Payback
Spencer County attic insulation, by the numbers
DOE classifies Spencer County as climate zone 4, mixed-humid — real heating and real cooling seasons both, roughly balanced across the year. Its recommended attic R-value for bare joists is 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 $1,418 a year — payback in roughly 2.5 years. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,222 a year on the heating side, $195 on cooling. By estimated insulation savings, Spencer County lands in the 47th percentile nationally. Zone 4 alone covers 825 counties in this dataset, and Spencer County comes in 349th by savings. Indiana averages $1,634/year across the counties tracked here; Spencer County comes in 13% lower.
Where these numbers come from
Spencer County's climate figures — 4,572 heating and 1,215 cooling degree days a year — are read from TELL CITY, IN US, 13.4 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Spencer County in the 47th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Spencer County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
Already have some insulation?
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $207/year saved — roughly 11 years to break even. Call this borderline rather than a clear win.
Getting it done in Spencer 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 Spencer County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Spencer 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.