Shiawassee County, MI Insulation Payback
Shiawassee County attic insulation, by the numbers
Shiawassee County sits in IECC climate zone 5 (Cold) — a real winter that drives most of the annual energy bill here. For a currently uninsulated attic, DOE and ENERGY STAR recommend building up to R-60. Going from R-2 to the recommended R-60 costs roughly $3,480 installed for a typical attic (about 1,000 sq ft), and pays for itself in about 1.8 years at an estimated $1,929/year saved. Topping up the attic pays for itself fast here.
Heating vs. cooling in Shiawassee County
Split it out and it's roughly $1,836 a year on the heating side, $93 on cooling. By estimated insulation savings, Shiawassee County lands in the 79th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Shiawassee County comes in 112th by savings. Michigan averages $2,064/year across the counties tracked here; Shiawassee County comes in 7% lower.
Where these numbers come from
Shiawassee County's climate figures — 6,868 heating and 578 cooling degree days a year — are read from OWOSSO WWTP, MI US, 4.8 miles away, NOAA's nearest 1991-2020 normals station. That combined heating-and-cooling load ranks Shiawassee County 683rd nationally by total degree days — the 78th percentile. One local detail the R-value alone won't tell you: Shiawassee County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
If Shiawassee County's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-49. That smaller top-up costs around $2,280 and saves an estimated $281/year — payback about 8.1 years. Call this borderline rather than a clear win.
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 Shiawassee County's estimated $1,929/year on the line.
Where these figures come from
Shiawassee County's R-60 target and its degree-day figures both come from named federal sources - see the methodology guide for exactly which ones. The guide to what R-value actually means explains why R-60 is the target here specifically.