Dubuque County, IA Insulation Payback
Dubuque County attic insulation, by the numbers
DOE classifies Dubuque 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. Going from R-2 to the recommended R-60 costs roughly $3,480 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 1.7 years at an estimated $1,997/year saved. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,894 a year on the heating side, $102 on cooling. By estimated insulation savings, Dubuque County lands in the 82th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Dubuque County comes in 47th by savings. Iowa averages $1,985/year across the counties tracked here; Dubuque County comes in 1% higher.
The climate data behind this
Dubuque County's climate figures — 7,084 heating and 638 cooling degree days a year — are read from DUBUQUE RGNL AP, IA US, 10 miles away, NOAA's nearest 1991-2020 normals station. By total degree days, Dubuque County sits at the 82th percentile nationally. One local detail the R-value alone won't tell you: Dubuque County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
Already have some insulation?
If Dubuque 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 $291/year — payback about 7.8 years. Worth doing on the numbers alone.
Next steps for a Dubuque 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 Dubuque County's estimated $1,997/year on the line.
Where these figures come from
Dubuque 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.