Grady County, OK Insulation Payback
Grady County attic insulation, by the numbers
DOE classifies Grady County as climate zone 3, mixed-humid — a genuine mix of cold winters and humid summers, with neither one dominating the bill. Its recommended attic R-value for bare joists is R-49. Topping up a typical 1,000-square-foot attic from bare joists (R-2) to R-49 runs an estimated $2,820, and saves about $1,273 a year in heating and cooling — a payback around 2.2 years.
Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $939 a year on the heating side, $334 on cooling. By estimated insulation savings, Grady County lands in the 36th percentile nationally. Zone 3 alone covers 690 counties in this dataset, and Grady County comes in 39th by savings. Oklahoma averages $1,260/year across the counties tracked here; Grady County comes in 1% higher.
Where these numbers come from
NOAA's Chickasha 2SSE Mesonet, OK US station, 1.7 miles from Grady County, supplies the 3,540 HDD and 2,094 CDD this estimate runs on. By total degree days, Grady County sits at the 43rd percentile nationally. One local detail the R-value alone won't tell you: Grady 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-38 runs about $1,620 for about $171/year saved — roughly 9.4 years to break even. Call this borderline rather than a clear win.
Next steps for a Grady County attic
Actual quotes will vary by attic access, existing debris, and whether the job needs air sealing first, so treat the $2,820 figure above as a planning number for Grady County, not a bid. Worth getting quotes from at least two local contractors before committing - most charge a $600 minimum regardless of job size.
Where these figures come from
Grady County's R-49 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-49 is the target here specifically.