Aransas County, TX Insulation Payback
Aransas County attic insulation, by the numbers
Aransas County sits in IECC climate zone 2 (Hot-Humid) — humid heat for much of the year, with cooling running far more than heating ever does. For a currently uninsulated attic, DOE and ENERGY STAR recommend building up to 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 $821 a year — payback in roughly 3.4 years. Topping up the attic pays for itself here.
Where the savings come from
Split it out and it's roughly $219 a year on the heating side, $601 on cooling. By estimated insulation savings, Aransas County lands in the 5th percentile nationally. Zone 2 alone covers 233 counties in this dataset, and Aransas County comes in 150th by savings. Texas averages $1,035/year across the counties tracked here; Aransas County comes in 21% lower.
Where these numbers come from
Aransas County's climate figures — 826 heating and 3,774 cooling degree days a year — are read from ROCKPORT ARANSAS CO AP, TX US, 5.5 miles away, NOAA's nearest 1991-2020 normals station. By total degree days, Aransas County sits at the 14th percentile nationally. One local detail the R-value alone won't tell you: Aransas County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
If the attic isn't bare
If Aransas 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 $111/year — payback about 14.7 years. Call this borderline rather than a clear win.
Next steps for a Aransas County attic
Actual quotes will vary by attic access, existing debris, and whether the job needs air sealing first. Treat the $2,820 figure above as a planning number for Aransas County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Where these figures come from
Aransas 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.