Portage County, WI Insulation Payback
Attic insulation payback for Portage County, WI
Portage County sits in IECC climate zone 6 (Cold) — cold enough that heating, not cooling, is what decides the bill. For a currently uninsulated attic, DOE and ENERGY STAR recommend building 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 $2,221 a year — payback in roughly 1.6 years. Hard to find a home improvement with a faster payback than this.
Heating vs. cooling in Portage County
Of that, about $2,149/year comes from reduced heating and $72/year from reduced cooling load through the ceiling. Portage County beats 91% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 459 counties DOE places in zone 6, Portage County ranks 170th. Against Wisconsin's own average of $2,200/year, Portage County runs 1% above that.
The climate data behind this
NOAA's STEVENS PT, WI US station, 4.9 miles from Portage County, supplies the 8,037 HDD and 451 CDD this estimate runs on. By total degree days, Portage County sits at the 91th percentile nationally. DOE also classifies Portage County as moisture regime A (humid) - ask a local contractor whether that changes the vapor-barrier approach for this job.
Already have some insulation?
If Portage 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 $324/year — payback about 7 years. Topping up the attic pays for itself here.
Getting it done in Portage 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 Portage County, not a bid - contractors typically charge a $600 minimum regardless of job size.
More on how this was built
Nothing here is a guess: the methodology guide names the DOE climate map and NOAA station data behind every number on this page. See the DIY vs. contractor guide for whether a job this size is realistic to do yourself.