Vermilion Parish, LA Insulation Payback
Vermilion Parish, LA: what topping up your attic actually costs
Vermilion Parish sits in IECC climate zone 2 (Hot-Humid) — long, muggy summers and mild winters, where cooling dominates the energy bill. For a currently uninsulated attic, DOE and ENERGY STAR recommend building up to R-49. Going from R-2 to the recommended R-49 costs roughly $2,820 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 3.4 years at an estimated $840/year saved. The math clears comfortably within a normal ownership horizon.
The breakdown behind the number
The estimated savings split roughly $443/year heating, $397/year cooling. Out of every 100 US counties tracked here, Vermilion Parish's savings potential beats roughly 6 of them. Within zone 2 specifically, it ranks 128th of 233 counties by estimated savings. Louisiana averages $906/year across the counties tracked here; Vermilion Parish comes in 7% lower.
Where these numbers come from
The heating and cooling degree days behind this estimate — 1,668 HDD and 2,492 CDD (base 65°F, 1991-2020 normals) — come from LELAND BOWMAN LOCK, LA US, the nearest NOAA station with published normals, 7.1 miles from Vermilion Parish's center. By total degree days, Vermilion Parish sits at the 4th percentile nationally. Vermilion Parish falls in DOE's moisture regime A (humid), a detail that affects vapor-barrier recommendations more than the R-value target itself.
If the attic isn't bare
If Vermilion Parish's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-38. That smaller top-up costs around $1,620 and saves an estimated $113/year — payback about 14.3 years. This one is a genuine toss-up, not a clear yes.
Getting it done in Vermilion Parish
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 Vermilion Parish, not a bid - contractors typically charge a $600 minimum regardless of job size.
Nothing here is a guess
Every figure on this page traces to DOE/IECC climate zones and NOAA degree-day normals, documented in the methodology guide. The guide to what R-value actually means explains why R-49 is the target here specifically.