Grenada County, MS Insulation Payback
Attic insulation payback for Grenada County, MS
DOE classifies Grenada County as climate zone 3, mixed-humid — real heating and real cooling seasons both, roughly balanced across the year. Its recommended attic R-value for bare joists is 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 $1,093 a year in heating and cooling — a payback around 2.6 years. Hard to find a home improvement with a faster payback than this.
The breakdown behind the number
Of that, about $769/year comes from reduced heating and $324/year from reduced cooling load through the ceiling. Grenada County beats 24% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 690 counties DOE places in zone 3, Grenada County ranks 248th. Against Mississippi's own average of $1,022/year, Grenada County runs 7% above that.
The climate data behind this
Grenada County's climate figures — 2,898 heating and 2,034 cooling degree days a year — are read from GRENADA, MS US, 0.9 miles away, NOAA's nearest 1991-2020 normals station. Combined heating and cooling load puts Grenada County in the 24th percentile of this 3,162-county dataset. DOE also classifies Grenada County as moisture regime A (humid) - ask a local contractor whether that changes the vapor-barrier approach for this job.
Already have some insulation?
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 $147/year saved (~11-year payback). It is close - the payback only just fits a reasonable timeframe.
Quotes and materials for this job
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 Grenada County, not a bid - contractors typically charge a $600 minimum regardless of job size.
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.