Crockett County, TN Insulation Payback
Crockett County, TN: what topping up your attic actually costs
Crockett County, Tennessee is zone 3 under DOE's climate map (Mixed-Humid), which means a genuine mix of cold winters and humid summers, with neither one dominating the bill. An uninsulated attic there should be built up to R-49. For an attic around 1,000 square feet, closing the gap from R-2 to R-49 costs around $2,820 and saves an estimated $1,237 a year — payback in roughly 2.3 years. That's about as fast as attic paybacks get.
The breakdown behind the number
The estimated savings split roughly $969/year heating, $268/year cooling. Out of every 100 US counties tracked here, Crockett County's savings potential beats roughly 34 of them. Within zone 3 specifically, it ranks 60th of 690 counties by estimated savings. Tennessee averages $1,258/year across the counties tracked here; Crockett County comes in 2% lower.
The climate data behind this
Crockett County's climate figures — 3,652 heating and 1,680 cooling degree days a year — are read from ALAMO 1 N, TN US, 1.7 miles away, NOAA's nearest 1991-2020 normals station. By total degree days, Crockett County sits at the 35th percentile nationally. Crockett County falls in DOE's moisture regime A (humid), a detail that affects vapor-barrier recommendations more than the R-value target itself.
Already have some insulation?
A shallower starting point changes the math: with R-11 already down, only the gap to R-38 needs filling, at roughly $1,620 for an estimated $167/year saved (~9.7-year payback). This one is a genuine toss-up, not a clear yes.
Quotes and materials for this job
Real bids depend on how easy the attic is to reach and whether old insulation needs removing first, so treat $2,820 as a starting estimate for a Crockett County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Nothing here is a guess
Every figure on this page traces to DOE/IECC climate zones and NOAA degree-day normals, documented in the methodology guide. The guide to what R-value actually means explains why R-49 is the target here specifically.