Travis County, TX Insulation Payback
Travis County, TX: what topping up your attic actually costs
Travis County sits in IECC climate zone 2 (Hot-Humid) — long, muggy summers and mild winters, where cooling dominates the energy bill. For a currently uninsulated attic, DOE and ENERGY STAR recommend building up to R-49. Topping up a typical 1,000-square-foot attic from bare joists (R-2) to R-49 runs an estimated $2,820, and saves about $944 a year in heating and cooling — a payback around 3 years. That's about as fast as attic paybacks get.
The breakdown behind the number
The estimated savings split roughly $504/year heating, $440/year cooling. Out of every 100 US counties tracked here, Travis County's savings potential beats roughly 13 of them. Within zone 2 specifically, it ranks 19th of 233 counties by estimated savings. Texas averages $1,035/year across the counties tracked here; Travis County comes in 9% lower.
Where these numbers come from
The heating and cooling degree days behind this estimate — 1,901 HDD and 2,761 CDD (base 65°F, 1991-2020 normals) — come from AUSTIN 6S, TX US, the nearest NOAA station with published normals, 2.7 miles from Travis County's center. That combined heating-and-cooling load ranks Travis County 2672nd nationally by total degree days — the 16th percentile. Travis County falls in DOE's moisture regime A (humid), a detail that affects vapor-barrier recommendations more than the R-value target itself.
The smaller top-up scenario
Already have a few inches up there? Topping R-11 up to R-38 runs about $1,620 for about $127/year saved — roughly 12.7 years to break even. This one is a genuine toss-up, not a clear yes.
Getting it done in Travis County
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 Travis County, not a bid - contractors typically charge a $600 minimum regardless of job size.
Nothing here is a guess
Every figure on this page traces to DOE/IECC climate zones and NOAA degree-day normals, documented in the methodology guide. The guide to what R-value actually means explains why R-49 is the target here specifically.