Washington County, RI Insulation Payback
Washington County attic insulation, by the numbers
Washington County, Rhode Island is zone 5 under DOE's climate map (Cold), which means cold enough that heating, not cooling, is what decides the bill. An uninsulated attic there should be built up to R-60. For an attic around 1,000 square feet, closing the gap from R-2 to R-60 costs around $3,480 and saves an estimated $1,722 a year — payback in roughly 2 years. Topping up the attic pays for itself fast here.
The breakdown behind the number
Split it out and it's roughly $1,651 a year on the heating side, $71 on cooling. By estimated insulation savings, Washington County lands in the 67th percentile nationally. Zone 5 alone covers 745 counties in this dataset, and Washington County comes in 439th by savings. Rhode Island averages $1,664/year across the counties tracked here; Washington County comes in 3% higher.
The climate data behind this
Washington County's climate figures — 6,173 heating and 443 cooling degree days a year — are read from KINGSTON 1 W, RI US, 6.9 miles away, NOAA's nearest 1991-2020 normals station. That combined heating-and-cooling load ranks Washington County 1134th nationally by total degree days — the 64th percentile. One local detail the R-value alone won't tell you: Washington County sits in moisture regime A (humid), which can affect the vapor-barrier choice.
The smaller top-up scenario
Already have a few inches up there? Topping R-11 up to R-49 runs about $2,280 for about $251/year saved — roughly 9.1 years to break even. Call this borderline rather than a clear win.
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 $3,480 as a starting estimate for a Washington County job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Washington 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.