Wake County, NC Insulation Payback
Wake County attic insulation, by the numbers
Wake County sits in IECC climate zone 4 (Mixed-Humid) — a genuine mix of cold winters and humid summers, with neither one dominating the bill. 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 $1,132 a year in heating and cooling — a payback around 3.1 years. Topping up the attic pays for itself here.
Heating vs. cooling in Wake County
Split it out and it's roughly $846 a year on the heating side, $286 on cooling. By estimated insulation savings, Wake County lands in the 27th percentile nationally. Zone 4 alone covers 825 counties in this dataset, and Wake County comes in 798th by savings. North Carolina averages $1,169/year across the counties tracked here; Wake County comes in 3% lower.
Wake County's actual weather, not a national average
The heating and cooling degree days behind this estimate — 3,165 HDD and 1,779 CDD (base 65°F, 1991-2020 normals) — come from RALEIGH STATE UNIV, NC US, the nearest NOAA station with published normals, 2.7 miles from Wake County's center. By total degree days, Wake County sits at the 24th percentile nationally. One local detail the R-value alone won't tell you: Wake 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-49 runs about $2,280 for about $165/year saved — roughly 13.8 years to break even. Call this borderline rather than a clear win.
Getting it done in Wake County
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 Wake County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Wake 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.