Green County, WI Insulation Payback
Green County, WI: what topping up your attic actually costs
Green County, Wisconsin is zone 6 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 $2,014 a year in heating and cooling — a payback around 1.7 years. That's about as fast as attic paybacks get.
Where the savings come from
The estimated savings split roughly $1,902/year heating, $112/year cooling. Out of every 100 US counties tracked here, Green County's savings potential beats roughly 83 of them. Within zone 6 specifically, it ranks 382nd of 459 counties by estimated savings. Wisconsin averages $2,200/year across the counties tracked here; Green County comes in 8% lower.
Green County's actual weather, not a national average
The heating and cooling degree days behind this estimate — 7,115 HDD and 697 CDD (base 65°F, 1991-2020 normals) — come from MONROE WWTP, WI US, the nearest NOAA station with published normals, 6.1 miles from Green County's center. That combined heating-and-cooling load ranks Green County 522nd nationally by total degree days — the 84th percentile. Green 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
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $294/year saved — roughly 7.8 years to break even. That is a solid payback as home upgrades go.
Getting it done in Green 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 Green County's estimated $2,014/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.