Clark County, MO Insulation Payback
Clark County attic insulation, by the numbers
Clark 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. 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 $1,755 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 $1,580 a year on the heating side, $175 on cooling. By estimated insulation savings, Clark County lands in the 70th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Clark County comes in 376th by savings. Missouri averages $1,534/year across the counties tracked here; Clark County comes in 14% higher.
Clark County's actual weather, not a national average
NOAA's DONNELLSON, IA US station, 18.6 miles from Clark County, supplies the 5,910 HDD and 1,089 CDD this estimate runs on. By total degree days, Clark County sits at the 71th percentile nationally. One local detail the R-value alone won't tell you: Clark County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $256/year saved — roughly 8.9 years to break even. Call this borderline rather than a clear win.
Next steps for a Clark County attic
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 Clark County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Clark 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.