Overton County, TN Insulation Payback
Overton County attic insulation, by the numbers
DOE classifies Overton County as climate zone 4, 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-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 2.7 years at an estimated $1,280/year saved. Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $1,075 a year on the heating side, $205 on cooling. By estimated insulation savings, Overton County lands in the 37th percentile nationally. Zone 4 alone covers 825 counties in this dataset, and Overton County comes in 623rd by savings. Tennessee averages $1,258/year across the counties tracked here; Overton County comes in 2% higher.
The climate data behind this
NOAA's LIVINGSTON RADIO WLIV, TN US station, 3.7 miles from Overton County, supplies the 4,019 HDD and 1,277 CDD this estimate runs on. That combined heating-and-cooling load ranks Overton County 2080th nationally by total degree days — the 34th percentile. One local detail the R-value alone won't tell you: Overton County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
Already have some insulation?
A shallower starting point changes the math: with R-11 already down, only the gap to R-49 needs filling, at roughly $2,280 for an estimated $187/year saved (~12.2-year payback). Call this borderline rather than a clear win.
Next steps for a Overton 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 Overton County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Overton 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.