Broward County, FL Insulation Payback
Broward County attic insulation, by the numbers
DOE classifies Broward County as climate zone 1, hot-humid — long, muggy summers and mild winters, where cooling dominates the energy bill. Its recommended attic R-value for bare joists is R-30. Topping up a typical 1,000-square-foot attic from bare joists (R-2) to R-30 runs an estimated $1,680, and saves about $696 a year in heating and cooling — a payback around 2.4 years. Topping up the attic pays for itself fast here.
The breakdown behind the number
Split it out and it's roughly $36 a year on the heating side, $660 on cooling. By estimated insulation savings, Broward County lands in the 2th percentile nationally. Zone 1 alone covers 81 counties in this dataset, and Broward County comes in 50th by savings. Florida averages $743/year across the counties tracked here; Broward County comes in 6% lower.
The climate data behind this
The heating and cooling degree days behind this estimate — 138 HDD and 4,256 CDD (base 65°F, 1991-2020 normals) — come from CORAL SPRINGS, FL US, the nearest NOAA station with published normals, 13.5 miles from Broward County's center. Combined heating and cooling load puts Broward County in the 9th percentile of this 3,162-county dataset. One local detail the R-value alone won't tell you: Broward County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
If the attic isn't bare
A shallower starting point changes the math: with R-11 already down, only the gap to R-25 needs filling, at roughly $840 for an estimated $76/year saved (~11.1-year payback). Call this borderline rather than a clear win.
Quotes and materials for this job
Real bids depend on how easy the attic is to reach and whether old insulation needs removing first, so treat $1,680 as a starting estimate for a Broward County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Broward County's R-30 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-30 is the target here specifically.