Attic insulation, air sealing, crawl spaces and walls for homes in South Berwick — starting with a free assessment that measures the R-value you actually have. The typical home here dates to the early-1980s, and 22% of its 3,172 homes went up before 1940.
South Berwick runs to about 32 square miles and roughly 7,670 people. It sits about 39 miles southwest of downtown Portland. Around 3,172 housing units sit inside those boundaries. The community dates back to 1814. We cover ZIP code 03908.
No completed job in South Berwick is logged in our records yet, and this page will say so until one is.
The typical home in South Berwick dates to around the early-1980s. Houses of this vintage usually got batts or blown fiber at whatever the standard of the day was, which is well short of what is recommended now. Most are one top-up away from being right.
We work across South Berwick rather than one corner of it — South Berwick Village, Central Square, Great Works, Agamenticus Station, Emerys Bridge, Oldfields, Jewett and Boyd Corner included. Construction and vintage change between them, sometimes by thirty years and a whole different framing method, which decides whether a wall can be dense-packed at all.
South Berwick, set off from Berwick in 1814, has some of the oldest houses in the area, including the Sarah Orne Jewett House of 1774 on Central Square and the Federal-style Hamilton House of about 1785. Its village center was listed on the National Register in 2010, and the town lies along the Salmon Falls River on the New Hampshire line.
The Census Bureau estimates 3,172 homes in South Berwick. 700 of them (22%) went up before 1940 — 18th of 64 places on this site for pre-1940 housing. The 1980s were the busiest decade, adding 835 of today's homes (26%); 44% predate 1980 and 18% were built in 2000 or later. For York County as a whole the pre-1940 share is 20%, so South Berwick sits above it.
Of 2,907 occupied homes, 7% heat with utility gas and 4% with electricity; another 20% burn propane or other tank gas. Electric heat here is less common than across the county (10%), and ranks 56th of 64 on this site. Efficiency Maine's insulation rebates do not depend on the fuel or the utility, but the fuel decides what the work saves, so the assessment asks how the house is heated.
78% of occupied homes are owner-occupied and 77% of all homes are single-family detached houses. On a housing mix like this, the likely starting points are the attic, which is where most houses here start.
| Built | Homes | Share | |
|---|---|---|---|
| Before 1940 | 700 | 22% | |
| 1940s | 80 | 3% | |
| 1950s | 245 | 8% | |
| 1960s | 95 | 3% | |
| 1970s | 264 | 8% | |
| 1980s | 835 | 26% | |
| 1990s | 377 | 12% | |
| 2000s | 295 | 9% | |
| 2010s | 196 | 6% | |
| 2020 or later | 85 | 3% |
3,172 homes, Census ACS 2020–2024 (B25034, B25040, B25003); 2,907 occupied.
1,212 of South Berwick's 3,172 homes (38%) were built in the 1980s and 1990s. The gaps in houses of that age are the parts nobody sealed: batts stuffed into the rim joist, bare spots over cathedral and tray ceilings, soffit vents buried with no baffles, can lights punched through the ceiling plane. A top-up plus a day of sealing usually covers it.
South Berwick enforces the Maine Uniform Building and Energy Code (2021 IECC with Maine amendments). South Berwick has applied the state code since December 1, 2010 (Chapter 60, Section 60-1), and its Code Enforcement page lists the 2021 residential code for one- and two-family homes.
That edition sets R-60 for the attic in new work, and R-30, or R-20 + R-10 continuous, or R-13 + R-15 continuous, or R-20 continuous for walls. The Department of Energy's recommendation for this climate zone is no lower: R60 for an attic with nothing in it, R49 where a few inches are already down.
Table R402.1.3 of the 2021 IECC for climate zone 6, with the wall row as Maine rewrote it (08-003 C.M.R.
Nothing South Berwick publishes settles this. Its permit lists name the work types it cares about, and insulation is not among them in either direction. South Berwick's list of work that needs no permit does not name insulation, and the town asks owners in the Historic District, or within 1,500 feet of a historic property, to contact the Code Enforcement Officer first. So we ask the department directly before the first day on site, and whatever comes back, pulling it is our job rather than yours.
The published number is 207-384-3301. The department page is here.
Permitting is on us, not on you.
Heating fuel in South Berwick, by the Census Bureau's count: fuel oil or kerosene in 60% of occupied homes, electricity in 4%, propane or tank gas in 20%, and 7% utility gas (Census ACS 2020–2024). The insulation money for a South Berwick house comes from Efficiency Maine, not the electric company. For a zone of 500 square feet or more it pays $2,000 at any income, $3,000 at moderate income and $4,000 at low income, and $150 to $300 more for attic air sealing. It applies to work completed on or after October 1, 2026 by one of its Residential Registered Vendors, and an attic qualifies only if it starts at R-21 or less. Income-qualified households in York County can apply to York County Community Action Corp (207-324-5762) for free weatherization through MaineHousing instead. Every condition is in the rebate guide. The York County page compares the towns.
Every layer of an insulated attic, explained
South Berwick borders Berwick, North Berwick, Wells, York, Eliot and Rollinsford, New Hampshire. These are the ones we also cover, each with its own energy code and permit rule:
Elsewhere in York County we also cover:
Maine sets the residential energy code statewide, so the attic figure is R-60 wherever it is published here; what changes is the permit desk, and 1 of the 7 publishes a permit rule for insulation.
| City | Energy code | Attic R required | Permit to insulate | Building dept. |
|---|---|---|---|---|
| South Berwick | Maine code, 2021 IECC | R-60 | Not published | 207-384-3301 |
| Berwick | Maine code, 2021 IECC | R-60 | Not published | 207-698-1101 |
| North Berwick | Maine code, 2021 IECC | R-60 | Not published | 207-676-3353 |
| Wells | Maine code, 2021 IECC | R-60 | Yes | 207-646-5187 |
| York | Maine code, 2021 IECC | R-60 | Not published | 207-363-1002 |
| Eliot | Maine code, 2021 IECC | R-60 | Not published | 207-439-1813 |
| Acton | Maine code, 2021 IECC | R-60 | Not published | 207-636-3131 |
All 29 York County jurisdictions side by side →
South Berwick enforces the Maine code, 2021 IECC, which sets R-60 for an attic in new work. That code also reaches work on existing houses, not only new ones.
Not on paper: South Berwick names neither a permit nor an exemption for insulation, so one call to the department at 207-384-3301 settles it first.
Efficiency Maine's: $2,000 per attic, wall or basement zone of 500 square feet or more at any income, $3,000 at moderate income and $4,000 at low income, plus $150 to $300 for attic air sealing, on work completed by one of its Residential Registered Vendors on or after October 1, 2026. The federal 25C credit ended for work placed in service after December 31, 2025.
The typical home in South Berwick dates to around the early-1980s; the Census Bureau's 2020-2024 median year built is 1982. Of its 3,172 homes, 22% went up before 1940 and 18% in 2000 or later. Half the homes here are older than that and half newer; yours may sit at either end.
Code and permit facts checked October 24, 2026, rebates October 24, 2026; housing: Census ACS 2020–2024. Sources: southberwickmaine.org (2, 3) · ecode360.com (2, 3) · maine.gov (2) · en.wikipedia.org (2) · www2.census.gov (2, 3) · prd-tnm.s3.amazonaws.com · efficiencymaine.com (2, 3, 4) · energystar.gov · data.census.gov. These change; confirm with the building department at 207-384-3301 or Efficiency Maine at 866-376-2463 first.
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