Caddo Parish, LA Insulation Payback
Caddo Parish, LA: what topping up your attic actually costs
DOE classifies Caddo Parish as climate zone 3, hot-humid — humid heat for much of the year, with cooling running far more than heating ever does. Its recommended attic R-value for bare joists is 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 $978 a year — payback in roughly 2.9 years. That's about as fast as attic paybacks get.
Where the savings come from
The estimated savings split roughly $517/year heating, $461/year cooling. Out of every 100 US counties tracked here, Caddo Parish's savings potential beats roughly 15 of them. Within zone 3 specifically, it ranks 518th of 690 counties by estimated savings. Louisiana averages $906/year across the counties tracked here; Caddo Parish comes in 8% higher.
Where these numbers come from
Caddo Parish's climate figures — 1,947 heating and 2,894 cooling degree days a year — are read from SHREVEPORT DWTN AP, LA US, 8.5 miles away, NOAA's nearest 1991-2020 normals station. That combined heating-and-cooling load ranks Caddo Parish 2498th nationally by total degree days — the 21th percentile. Caddo 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
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 $132/year saved (~12.3-year payback). This one is a genuine toss-up, not a clear yes.
Getting it done in Caddo Parish
Get more than one quote before committing. Attic access and any needed air sealing move the price around, and most contractors won't take a job below roughly $600 regardless of size - worth asking upfront given Caddo Parish's estimated $978/year on the line.
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.