Woodbury County, IA Insulation Payback
Woodbury County attic insulation, by the numbers
Woodbury County sits in IECC climate zone 5 (Cold) — winters that dominate the energy bill, with cooling a minor factor. For a currently uninsulated attic, DOE and ENERGY STAR recommend building 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 $2,008 a year in heating and cooling — a payback around 1.7 years. Topping up the attic pays for itself fast here.
The breakdown behind the number
Split it out and it's roughly $1,871 a year on the heating side, $137 on cooling. By estimated insulation savings, Woodbury County lands in the 83th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Woodbury County comes in 40th by savings. Iowa averages $1,985/year across the counties tracked here; Woodbury County comes in 1% higher.
The climate data behind this
NOAA's SIOUX CITY ANG, IA US station, 16.6 miles from Woodbury County, supplies the 6,998 HDD and 850 CDD this estimate runs on. Combined heating and cooling load puts Woodbury County in the 84th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Woodbury County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
Already have some insulation?
If Woodbury 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 $293/year — payback about 7.8 years. Worth doing on the numbers alone.
Getting it done in Woodbury County
Real bids depend on how easy the attic is to reach and whether old insulation needs removing first, so treat $3,480 as a starting estimate for a Woodbury County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Woodbury 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.