Richmond County, NC Insulation Payback
Richmond County attic insulation, by the numbers
DOE classifies Richmond 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. Going from R-2 to the recommended R-49 costs roughly $2,820 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 2.6 years at an estimated $1,081/year saved. Topping up the attic pays for itself fast here.
The breakdown behind the number
Split it out and it's roughly $749 a year on the heating side, $332 on cooling. By estimated insulation savings, Richmond County lands in the 23th percentile nationally. Zone 3 alone covers 690 counties in this dataset, and Richmond County comes in 287th by savings. North Carolina averages $1,169/year across the counties tracked here; Richmond County comes in 8% lower.
Richmond County's actual weather, not a national average
The heating and cooling degree days behind this estimate — 2,822 HDD and 2,082 CDD (base 65°F, 1991-2020 normals) — come from HAMLET, NC US, the nearest NOAA station with published normals, 8.9 miles from Richmond County's center. That combined heating-and-cooling load ranks Richmond County 2445th nationally by total degree days — the 23th percentile. One local detail the R-value alone won't tell you: Richmond County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Richmond County's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-38. That smaller top-up costs around $1,620 and saves an estimated $146/year — payback about 11.1 years. Call this borderline rather than a clear win.
Next steps for a Richmond County attic
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 Richmond County's estimated $1,081/year on the line.
Where these figures come from
Richmond 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.