Brunswick County, NC Insulation Payback
Brunswick County attic insulation, by the numbers
DOE classifies Brunswick County as climate zone 3, hot-humid — humid heat for much of the year, with cooling running far more than heating ever does. Its recommended attic R-value for bare joists is 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 $942 a year — payback in roughly 3 years.
Topping up the attic pays for itself fast here.
Where the savings come from
Split it out and it's roughly $644 a year on the heating side, $297 on cooling. By estimated insulation savings, Brunswick County lands in the 12th percentile nationally. Zone 3 alone covers 690 counties in this dataset, and Brunswick County comes in 589th by savings. North Carolina averages $1,169/year across the counties tracked here; Brunswick County comes in 19% lower.
Brunswick County's actual weather, not a national average
NOAA's Shallotte AG, NC US station, 12 miles from Brunswick County, supplies the 2,429 HDD and 1,865 CDD this estimate runs on. Combined heating and cooling load puts Brunswick County in the 6th percentile of this 3,171-county dataset. One local detail the R-value alone won't tell you: Brunswick County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
If the attic isn't bare
Already have a few inches up there? Topping R-11 up to R-38 runs about $1,620 for about $127/year saved — roughly 12.8 years to break even. Call this borderline rather than a clear win.
Next steps for a Brunswick County attic
Actual quotes will vary by attic access, existing debris, and whether the job needs air sealing first, so treat the $2,820 figure above as a planning number for Brunswick County, not a bid. Worth getting quotes from at least two local contractors before committing - most charge a $600 minimum regardless of job size.
Where these figures come from
Brunswick 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.