Mobile County, AL Insulation Payback
Mobile County attic insulation, by the numbers
Mobile County, Alabama is zone 2 under DOE's climate map (Hot-Humid), which means long, muggy summers and mild winters, where cooling dominates the energy bill. An uninsulated attic there should be built up to R-49. For an attic around 1,000 square feet, closing the gap from R-2 to R-49 costs around $2,820 and saves an estimated $843 a year — payback in roughly 3.3 years. Topping up the attic pays for itself here.
Where the savings come from
Split it out and it's roughly $429 a year on the heating side, $414 on cooling. By estimated insulation savings, Mobile County lands in the 6th percentile nationally. Zone 2 alone covers 233 counties in this dataset, and Mobile County comes in 123rd by savings. Alabama averages $1,001/year across the counties tracked here; Mobile County comes in 16% lower.
Mobile County's actual weather, not a national average
The heating and cooling degree days behind this estimate — 1,616 HDD and 2,599 CDD (base 65°F, 1991-2020 normals) — come from MOBILE, AL US, the nearest NOAA station with published normals, 2.6 miles from Mobile County's center. That combined heating-and-cooling load ranks Mobile County 3010th nationally by total degree days — the 5th percentile. One local detail the R-value alone won't tell you: Mobile County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
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 $114/year saved (~14.3-year payback). Call this borderline rather than a clear win.
Getting it done in Mobile County
Real bids depend on how easy the attic is to reach and whether old insulation needs removing first, so treat $2,820 as a starting estimate for a Mobile County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Mobile 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.