Major County, OK Insulation Payback
Major County, OK: what topping up your attic actually costs
Major County sits in IECC climate zone 3 (Mixed-Humid) — real heating and real cooling seasons both, roughly balanced across the year. 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 2.1 years at an estimated $1,353/year saved. That's about as fast as attic paybacks get.
Heating vs. cooling in Major County
The estimated savings split roughly $1,026/year heating, $327/year cooling. Out of every 100 US counties tracked here, Major County's savings potential beats roughly 42 of them. Within zone 3 specifically, it ranks 13th of 690 counties by estimated savings. Oklahoma averages $1,260/year across the counties tracked here; Major County comes in 7% higher.
Where these numbers come from
The heating and cooling degree days behind this estimate — 3,868 HDD and 2,049 CDD (base 65°F, 1991-2020 normals) — come from FAIRVIEW 1W MESONET, OK US, the nearest NOAA station with published normals, 4.2 miles from Major County's center. That combined heating-and-cooling load ranks Major County 1584th nationally by total degree days — the 50th percentile. Major County falls in DOE's moisture regime A (humid), a detail that affects vapor-barrier recommendations more than the R-value target itself.
The smaller top-up scenario
Already have a few inches up there? Topping R-11 up to R-38 runs about $1,620 for about $182/year saved — roughly 8.9 years to break even. This one is a genuine toss-up, not a clear yes.
Quotes and materials for this job
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 Major County's estimated $1,353/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.