Gloucester County, NJ Insulation Payback
Gloucester County attic insulation, by the numbers
DOE classifies Gloucester County as climate zone 4, mixed-humid — real heating and real cooling seasons both, roughly balanced across the year. Its recommended attic R-value for bare joists is 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 $1,473 a year in heating and cooling — a payback around 2.4 years. Topping up the attic pays for itself fast here.
Heating vs. cooling in Gloucester County
Split it out and it's roughly $1,286 a year on the heating side, $188 on cooling. By estimated insulation savings, Gloucester County lands in the 51th percentile nationally. Zone 4 alone covers 825 counties in this dataset, and Gloucester County comes in 224th by savings. New Jersey averages $1,541/year across the counties tracked here; Gloucester County comes in 4% lower.
The climate data behind this
NOAA's GLASSBORO 2 NE, NJ US station, 2.8 miles from Gloucester County, supplies the 4,809 HDD and 1,168 CDD this estimate runs on. Combined heating and cooling load puts Gloucester County in the 51th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Gloucester County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Gloucester County's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-49. That smaller top-up costs around $2,280 and saves an estimated $215/year — payback about 10.6 years. Call this borderline rather than a clear win.
Next steps for a Gloucester 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 Gloucester County's estimated $1,473/year on the line.
Where these figures come from
Gloucester 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.