York County, SC Insulation Payback
York County, SC: what topping up your attic actually costs
York 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. 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 $1,167 a year — payback in roughly 2.4 years. That's about as fast as attic paybacks get.
The breakdown behind the number
The estimated savings split roughly $917/year heating, $249/year cooling. Out of every 100 US counties tracked here, York County's savings potential beats roughly 29 of them. Within zone 3 specifically, it ranks 133rd of 690 counties by estimated savings. South Carolina averages $1,016/year across the counties tracked here; York County comes in 15% higher.
York County's actual weather, not a national average
York County's climate figures — 3,457 heating and 1,565 cooling degree days a year — are read from YORK 5 SSE, SC US, 3.4 miles away, NOAA's nearest 1991-2020 normals station. By total degree days, York County sits at the 27th percentile nationally. York County falls in DOE's moisture regime A (humid), a detail that affects vapor-barrier recommendations more than the R-value target itself.
Already have some insulation?
Already have a few inches up there? Topping R-11 up to R-38 runs about $1,620 for about $157/year saved — roughly 10.3 years to break even. This one is a genuine toss-up, not a clear yes.
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 York County job, not a quote. Expect at least a $600 minimum charge from most contractors.
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.