Suffolk County, MA Insulation Payback
Attic insulation payback for Suffolk County, MA
Suffolk County sits in IECC climate zone 5 (Cold) — cold enough that heating, not cooling, is what decides the bill. For a currently uninsulated attic, DOE and ENERGY STAR recommend building up to R-60. Topping up a typical 1,000-square-foot attic from bare joists (R-2) to R-60 runs an estimated $3,480, and saves about $1,611 a year in heating and cooling — a payback around 2.2 years. Hard to find a home improvement with a faster payback than this.
The breakdown behind the number
Of that, about $1,483/year comes from reduced heating and $129/year from reduced cooling load through the ceiling. Suffolk County beats 60% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 745 counties DOE places in zone 5, Suffolk County ranks 630th. Against Massachusetts's own average of $1,728/year, Suffolk County runs 7% below that.
The climate data behind this
The heating and cooling degree days behind this estimate — 5,545 HDD and 802 CDD (base 65°F, 1991-2020 normals) — come from BOSTON LOGAN INTL AP, MA US, the nearest NOAA station with published normals, 1.6 miles from Suffolk County's center. That combined heating-and-cooling load ranks Suffolk County 1303rd nationally by total degree days — the 59th percentile. DOE also classifies Suffolk County as moisture regime A (humid) - ask a local contractor whether that changes the vapor-barrier approach for this job.
Already have some insulation?
If Suffolk 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 $235/year — payback about 9.7 years. It is close - the payback only just fits a reasonable timeframe.
Quotes and materials for this job
Actual quotes will vary by attic access, existing debris, and whether the job needs air sealing first. Treat the $3,480 figure above as a planning number for Suffolk County, not a bid - contractors typically charge a $600 minimum regardless of job size.
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.