Castro County, TX Insulation Payback
Attic insulation payback for Castro County, TX
Castro County, Texas is zone 4 under DOE's climate map (Mixed-Dry), which means dry heat in summer giving way to a properly cold winter. An uninsulated attic there should be built up to R-60. For an attic around 1,000 square feet, closing the gap from R-2 to R-60 costs around $3,480 and saves an estimated $1,348 a year — payback in roughly 2.6 years. Hard to find a home improvement with a faster payback than this.
Heating vs. cooling in Castro County
Of that, about $1,132/year comes from reduced heating and $215/year from reduced cooling load through the ceiling. Castro County beats 42% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 825 counties DOE places in zone 4, Castro County ranks 490th. Against Texas's own average of $1,035/year, Castro County runs 30% above that.
The climate data behind this
Castro County's climate figures — 4,235 heating and 1,340 cooling degree days a year — are read from DIMMITT 2 N, TX US, 4.7 miles away, NOAA's nearest 1991-2020 normals station. By total degree days, Castro County sits at the 41th percentile nationally. DOE also classifies Castro County as moisture regime B (dry) - ask a local contractor whether that changes the vapor-barrier approach for this job.
Already have some insulation?
If Castro 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 $197/year — payback about 11.6 years. It is close - the payback only just fits a reasonable timeframe.
Getting it done in Castro 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 Castro County job, not a quote. Expect at least a $600 minimum charge from most contractors.
More on how this was built
Nothing here is a guess: the methodology guide names the DOE climate map and NOAA station data behind every number on this page. See the DIY vs. contractor guide for whether a job this size is realistic to do yourself.