Hancock County, IL Insulation Payback
Attic insulation payback for Hancock County, IL
DOE classifies Hancock County as climate zone 5, cold — winters that dominate the energy bill, with cooling a minor factor. 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 $1,683 a year — payback in roughly 2.1 years. Hard to find a home improvement with a faster payback than this.
Where the savings come from
Of that, about $1,495/year comes from reduced heating and $188/year from reduced cooling load through the ceiling. Hancock County beats 65% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 745 counties DOE places in zone 5, Hancock County ranks 511th. Against Illinois's own average of $1,642/year, Hancock County runs 2% above that.
The climate data behind this
The heating and cooling degree days behind this estimate — 5,590 HDD and 1,170 CDD (base 65°F, 1991-2020 normals) — come from BENTLEY, IL US, the nearest NOAA station with published normals, 4.9 miles from Hancock County's center. By total degree days, Hancock County sits at the 67th percentile nationally. DOE also classifies Hancock County as moisture regime A (humid) - ask a local contractor whether that changes the vapor-barrier approach for this job.
The smaller top-up scenario
If Hancock 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 $245/year — payback about 9.3 years. It is close - the payback only just fits a reasonable timeframe.
Next steps for a Hancock County attic
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 Hancock County's estimated $1,683/year on the line.
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.