Millard County, UT Insulation Payback
Attic insulation payback for Millard County, UT
DOE classifies Millard County as climate zone 5, cold — cold enough that heating, not cooling, is what decides the bill. Its recommended attic R-value for bare joists is R-60. Going from R-2 to the recommended R-60 costs roughly $3,480 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 2.1 years at an estimated $1,685/year saved. Hard to find a home improvement with a faster payback than this.
The breakdown behind the number
Of that, about $1,563/year comes from reduced heating and $122/year from reduced cooling load through the ceiling. Millard County beats 65% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 745 counties DOE places in zone 5, Millard County ranks 510th. Against Utah's own average of $1,791/year, Millard County runs 6% below that.
Where these numbers come from
NOAA's BLACK ROCK, UT US station, 19.7 miles from Millard County, supplies the 5,846 HDD and 760 CDD this estimate runs on. That combined heating-and-cooling load ranks Millard County 1144th nationally by total degree days — the 64th percentile. DOE also classifies Millard County as moisture regime B (dry) - ask a local contractor whether that changes the vapor-barrier approach for this job.
The smaller top-up scenario
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $246/year saved — roughly 9.3 years to break even. It is close - the payback only just fits a reasonable timeframe.
Quotes and materials for this job
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 Millard County's estimated $1,685/year on the line.
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.