Hancock County, TN Insulation Payback
Hancock County attic insulation, by the numbers
Hancock County sits in IECC climate zone 4 (Mixed-Humid) — real heating and real cooling seasons both, roughly balanced across the year. 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 $1,301 a year in heating and cooling — a payback around 2.7 years. Topping up the attic pays for itself fast here.
The breakdown behind the number
Split it out and it's roughly $1,128 a year on the heating side, $173 on cooling. By estimated insulation savings, Hancock County lands in the 39th percentile nationally. Zone 4 alone covers 825 counties in this dataset, and Hancock County comes in 578th by savings. Tennessee averages $1,258/year across the counties tracked here; Hancock County comes in 3% higher.
Where these numbers come from
The heating and cooling degree days behind this estimate — 4,217 HDD and 1,080 CDD (base 65°F, 1991-2020 normals) — come from ROGERSVILLE 1 NE, TN US, the nearest NOAA station with published normals, 15.4 miles from Hancock County's center. By total degree days, Hancock County sits at the 35th percentile nationally. One local detail the R-value alone won't tell you: Hancock County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
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 $190/year saved (~12-year payback). Call this borderline rather than a clear win.
Next steps for a Hancock 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 Hancock County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Hancock 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.