Terrebonne Parish, LA Insulation Payback
Is attic insulation worth it in Terrebonne Parish, LA?
Terrebonne Parish sits in IECC climate zone 2 (Hot-Humid) — summers that stay hot and humid while winters barely register on the energy bill. For a currently uninsulated attic, DOE and ENERGY STAR recommend building 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 $805 a year — payback in roughly 3.5 years. That is a solid payback as home upgrades go.
Where the savings come from
Heating accounts for about $332/year of that and cooling about $473/year — Terrebonne Parish needs both. Nationally, Terrebonne Parish ranks in the 4th percentile for insulation savings potential. Compared only against its own climate zone, Terrebonne Parish places 170th out of 233. Against Louisiana's own average of $906/year, Terrebonne Parish runs 11% below that.
Where these numbers come from
Terrebonne Parish's climate figures — 1,250 heating and 2,969 cooling degree days a year — are read from HOUMA, LA US, 21.3 miles away, NOAA's nearest 1991-2020 normals station. That combined heating-and-cooling load ranks Terrebonne Parish 3008th nationally by total degree days — the 5th percentile. Its moisture regime is classified humid, which matters for whether the attic needs a vapor retarder as part of the job — worth asking a contractor about locally.
If the attic isn't bare
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 $108/year saved (~14.9-year payback). Whether that is worth it depends on how long you plan to stay.
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 $2,820 as a starting estimate for a Terrebonne Parish job, not a quote. Expect at least a $600 minimum charge from most contractors.
Terrebonne Parish's numbers, sourced
The methodology guide lists exactly which DOE and NOAA sources feed Terrebonne Parish's numbers, and where the cost assumptions come from. See the DIY vs. contractor guide for whether a job this size is realistic to do yourself.