Washington County, ME Insulation Payback
Attic insulation payback for Washington County, ME
DOE classifies Washington County as climate zone 6, cold — cold enough that heating, not cooling, is what decides the bill. Its recommended attic R-value for bare joists is 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 $2,117 a year — payback in roughly 1.6 years. Hard to find a home improvement with a faster payback than this.
Heating vs. cooling in Washington County
Of that, about $2,075/year comes from reduced heating and $42/year from reduced cooling load through the ceiling. Washington County beats 87% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 459 counties DOE places in zone 6, Washington County ranks 279th. Against Maine's own average of $2,159/year, Washington County runs 2% below that.
Where these numbers come from
The heating and cooling degree days behind this estimate — 7,761 HDD and 260 CDD (base 65°F, 1991-2020 normals) — come from WESLEY, ME US, the nearest NOAA station with published normals, 3 miles from Washington County's center. By total degree days, Washington County sits at the 86th percentile nationally. DOE also classifies Washington County as moisture regime A (humid) - ask a local contractor whether that changes the vapor-barrier approach for this job.
If the attic isn't bare
A shallower starting point changes the math: with R-11 already down, only the gap to R-49 needs filling, at roughly $2,280 for an estimated $309/year saved (~7.4-year payback). Topping up the attic pays for itself here.
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.
More on how this was built
Nothing here is a guess: the methodology guide names the DOE climate map and NOAA station data behind every number on this page. See the DIY vs. contractor guide for whether a job this size is realistic to do yourself.