Iron County, UT Insulation Payback
Iron County attic insulation, by the numbers
DOE classifies Iron County as climate zone 5, cold — a real winter that drives most of the annual energy bill here. 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 $1,714 a year — payback in roughly 2 years. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,605 a year on the heating side, $109 on cooling. By estimated insulation savings, Iron County lands in the 67th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Iron County comes in 459th by savings. Utah averages $1,791/year across the counties tracked here; Iron County comes in 4% lower.
The climate data behind this
Iron County's climate figures — 6,002 heating and 678 cooling degree days a year — are read from CEDAR CITY MUNI AP, UT US, 18.1 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Iron County in the 65th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Iron County sits in moisture regime B (dry), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Iron 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 $250/year — payback about 9.1 years. Call this borderline rather than a clear win.
Next steps for a Iron County attic
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 Iron County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Iron 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.