Lamar County, GA Insulation Payback
Lamar County attic insulation, by the numbers
DOE classifies Lamar County as climate zone 3, mixed-humid — real heating and real cooling seasons both, roughly balanced across the year. 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 $978 a year in heating and cooling — a payback around 2.9 years. Topping up the attic pays for itself fast here.
Heating vs. cooling in Lamar County
Split it out and it's roughly $677 a year on the heating side, $301 on cooling. By estimated insulation savings, Lamar County lands in the 15th percentile nationally. Zone 3 alone covers 690 counties in this dataset, and Lamar County comes in 515th by savings. Georgia averages $974/year across the counties tracked here; Lamar County comes in 0% higher.
Lamar County's actual weather, not a national average
Lamar County's climate figures — 2,553 heating and 1,889 cooling degree days a year — are read from THE ROCK RCH, GA US, 9 miles away, NOAA's nearest 1991-2020 normals station. By total degree days, Lamar County sits at the 10th percentile nationally. One local detail the R-value alone won't tell you: Lamar County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
If the attic isn't bare
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 $132/year saved (~12.3-year payback). Call this borderline rather than a clear win.
Getting it done in Lamar County
Get more than one quote before committing. Attic access and any needed air sealing move the price around, and most contractors won't take a job below roughly $600 regardless of size - worth asking upfront given Lamar County's estimated $978/year on the line.
Where these figures come from
Lamar 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.