Grimes County, TX Insulation Payback
Grimes County attic insulation, by the numbers
Grimes 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. Going from R-2 to the recommended R-49 costs roughly $2,820 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 3.1 years at an estimated $921/year saved. Topping up the attic pays for itself here.
The breakdown behind the number
Split it out and it's roughly $464 a year on the heating side, $456 on cooling. By estimated insulation savings, Grimes County lands in the 11th percentile nationally. Zone 2 alone covers 233 counties in this dataset, and Grimes County comes in 30th by savings. Texas averages $1,035/year across the counties tracked here; Grimes County comes in 11% lower.
The climate data behind this
NOAA's WASHINGTON SP, TX US station, 18.3 miles from Grimes County, supplies the 1,750 HDD and 2,864 CDD this estimate runs on. Combined heating and cooling load puts Grimes County in the 14th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Grimes County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
A shallower starting point changes the math: with R-11 already down, only the gap to R-38 needs filling, at roughly $1,620 for an estimated $124/year saved (~13.1-year payback). Call this borderline rather than a clear win.
Getting it done in Grimes County
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 Grimes County's estimated $921/year on the line.
Where these figures come from
Grimes 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.