Insulation and air sealing for Cape Elizabeth homes: attics, crawl spaces, rim joists and walls, starting with a free assessment of the R-value you actually have. The typical home here dates to the late-1960s, and 19% of its 3,981 homes went up before 1940.
Cape Elizabeth runs to about 15 square miles and roughly 9,606 people. It sits about 7 miles southeast of downtown Portland. That is roughly 3,981 housing units. The community dates back to 1765. We cover ZIP code 04107.
Our job history shows nothing in Cape Elizabeth so far. Plenty of sites will show you a number here anyway.
The typical home in Cape Elizabeth dates to around the late-1960s. Postwar building here often meant three or four inches of fiberglass and no attempt at air sealing. If nobody has touched it since, that is what is still up there.
We work across Cape Elizabeth rather than one corner of it — Cape Cottage, Two Lights, Kettle Cove, Pond Cove, Shore Acres, Bowery Beach, Spurwink Shores, Oakhurst, Delano Park and Elizabeth Park 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.
An oceanfront town south of Portland Harbor, home to Portland Head Light, the oldest lighthouse in Maine, and three coastal parks: Fort Williams, Two Lights and Crescent Beach. South Portland split off in 1895 as the commercial and industrial north and the rural south grew apart, leaving Cape Elizabeth with the rural southern part.
The Census Bureau estimates 3,981 homes in Cape Elizabeth. 769 of them (19%) went up before 1940 — 25th of 64 places on this site for pre-1940 housing. More of today's homes date from before 1940 than from any single decade since, and 66% predate 1980. For Cumberland County as a whole the pre-1940 share is 23%, so Cape Elizabeth sits below it.
Of 3,732 occupied homes, 11% heat with utility gas and 12% with electricity; another 11% burn propane or other tank gas. Electric heat here is less common than across the county (15%), and ranks 18th of 64 on this site. The heating fuel does not change the Efficiency Maine rebate, but it does change what each inch of insulation is worth, which is why the boiler, furnace or heat pump is the first thing an assessment looks at.
88% of occupied homes are owner-occupied and 90% of all homes are single-family detached houses. On a housing mix like this, the likely starting points are an attic top-up over postwar fiberglass.
| Built | Homes | Share | |
|---|---|---|---|
| Before 1940 | 769 | 19% | |
| 1940s | 446 | 11% | |
| 1950s | 354 | 9% | |
| 1960s | 644 | 16% | |
| 1970s | 413 | 10% | |
| 1980s | 518 | 13% | |
| 1990s | 543 | 14% | |
| 2000s | 136 | 3% | |
| 2010s | 114 | 3% | |
| 2020 or later | 44 | 1% |
3,981 homes, Census ACS 2020–2024 (B25034, B25040, B25003); 3,732 occupied.
1,411 of Cape Elizabeth's 3,981 homes (35%) date from 1950 through 1979. The leaks in houses of that era repeat: nothing over the top plates, wire and pipe holes left open, an unsealed hatch, a bath fan venting into the attic, and in ranches and split-levels, heat lost at the garage ceiling and over cantilevered floors. Sealing the plates, holes and fans comes before any more fiber, and it is usually a day's work, not a renovation.
Cape Elizabeth enforces the Maine Uniform Building and Energy Code (2021 IECC with Maine amendments). The town's Code Enforcement FAQ lists the 2021 International Energy Conservation Code as part of the state code in force since April 7, 2025, and Chapter 6 of the Town Code carries the town's own design table.
Under that edition the required attic value for new work here is R-60, and walls R-30, or R-20 + R-10 continuous, or R-13 + R-15 continuous, or R-20 continuous. For comparison, the Department of Energy recommends R60 for an uninsulated attic in climate zone 6A, where Cape Elizabeth sits, and R49 where there are already a few inches up there.
The 2021 IECC insulation table (R402.1.3), climate zone 6; Maine's energy chapter changed the wood-frame wall entry and left the attic at R-60.
There is no published answer for Cape Elizabeth. Neither the permit-required list nor the exemption list mentions insulation or air sealing at all. Cape Elizabeth's FAQ requires a permit for construction and structural alteration, but not for ordinary repairs that leave walls, beams, bearing supports and exits alone; it does not name insulation. That silence is not permission and it is not a prohibition. We settle it with a phone call before the crew is scheduled.
The published number is 207-799-1619. The department page is here.
Permitting is on us, not on you.
Heating fuel in Cape Elizabeth, by the Census Bureau's count: fuel oil or kerosene in 64% of occupied homes, electricity in 12%, propane or tank gas in 11%, and 11% utility gas (Census ACS 2020–2024). For Cape Elizabeth homeowners the rebate is Efficiency Maine's: $2,000 for each attic, wall or basement zone of 500 square feet or more at any income ($3,000 moderate, $4,000 low income), with $150 to $300 for attic air sealing on top. 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 Cumberland County can apply to Community Concepts Inc (207-795-4065) for free weatherization through MaineHousing instead. The Cumberland County page and the rebate guide carry the full rules.
Every layer of an insulated attic, explained
Cape Elizabeth borders South Portland, Scarborough, Portland, Atlantic Ocean and Casco Bay. These are the ones we also cover, each with its own energy code and permit rule:
Elsewhere in Cumberland 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 2 of the 7 publish a permit rule for insulation.
| City | Energy code | Attic R required | Permit to insulate | Building dept. |
|---|---|---|---|---|
| Cape Elizabeth | Maine code, 2021 IECC | R-60 | Not published | 207-799-1619 |
| South Portland | Maine code, 2021 IECC | R-60 | Not published | 207-767-7603 |
| Scarborough | Maine code, 2021 IECC | R-60 | Not published | 207-730-4040 |
| Portland | Maine code, 2021 IECC | R-60 | Not published | 207-874-8703 |
| Baldwin | Not published | — | Not for an attic top-up | 207-625-3581 |
| Bridgton | Maine code, 2021 IECC | R-60 | Not for an attic top-up | 207-803-9963 |
| Brunswick | Maine code, 2021 IECC | R-60 | Not published | 207-725-6660 |
All 25 Cumberland County jurisdictions side by side →
Cape Elizabeth 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.
Cape Elizabeth has not published a rule for it; the building department at 207-799-1619 is called before the job starts.
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 Cape Elizabeth dates to around the late-1960s; the Census Bureau's 2020-2024 median year built is 1967. Of its 3,981 homes, 19% went up before 1940 and 7% in 2000 or later. That is a median across the whole place, so your own house may be older or newer.
Code and permit facts checked October 24, 2026, rebates October 24, 2026; housing: Census ACS 2020–2024. Sources: capeelizabeth.gov (2, 3, 4) · maine.gov (2) · en.wikipedia.org (2) · zip-codes.com · tigerweb.geo.census.gov · efficiencymaine.com (2, 3, 4) · energystar.gov · data.census.gov. These change; confirm with the building department at 207-799-1619 or Efficiency Maine at 866-376-2463 first.
Free assessment, measured at the hatch, with the photographs and the number in writing.
Book my free assessment →