The 1950s built more of Coventry than any other decade: 994 homes, 19.4% of the town’s 5,120 housing units, with 483 more from the 1940s. Together the 1940s and 50s account for 28.8% of the stock, a larger share than the 1960s and 70s at 18.5%. The median home dates from 1967, and 61.7% of Coventry’s housing was standing before 1980.
It is a town of owned, detached houses: 90.3% of units are single-family detached and 90.1% of occupied homes are owner-occupied. Fuel oil or kerosene heats 63.8% of them, electricity 13.9%, bottled gas 12.4% and wood 5.2%. Connecticut Natural Gas is the gas company on record, but utility gas heats 1.6% of homes.
That points to three kinds of house: the small post-war cape or ranch, the North Coventry raised ranch and split-level, and the larger house built after 1990, plus 735 homes from before 1940.
The houses we insulate in Coventry
The 1940s and 50s houses are mostly one-and-a-half-story capes and one-story ranches. The cape is the more troublesome of the two. Its upstairs bedrooms sit inside the roof, walled off from the eaves by short knee walls. Behind each knee wall is a triangle of unheated attic, and the floor joists of the bedroom run straight through it, open to that cold space, so winter air slides under the bedroom floor. The sloped ceiling above holds a thin batt pressed against the roof boards. Above is a flat attic too low to crawl, with a few inches of old insulation.
The ranch of the same age is simpler: one long attic over the whole house, often with settled loose-fill, a kitchen fan or bath fan venting into it, and a chimney chase with an open gap around it. Where either house sits partly over a crawl space or an added room sits on piers, the floor above that space is its own heat leak.
The 469 homes of the 1960s and 479 of the 1970s include the tract houses of North Coventry, raised ranches and split-levels on one-acre lots. The split-level is worth describing because it has more joints than any other house. The upper bedroom wing sits over a half-buried family room; the living wing sits beside it at a third height; the attic steps down over the middle, leaving a vertical wall of framing open to the attic; and the garage often tucks under the bedrooms. Each change of level is a place where air moves freely from inside to outside.
The 687 homes of the 1980s are mostly colonials and contemporaries. The 586 of the 1990s and the 13.4% built since 2000 include North Coventry’s larger houses on two-acre lots: insulated walls, open two-story foyers, bonus rooms, and attics insulated but never sealed.
With 63.8% of homes on oil and 12.4% on propane, most Coventry heat arrives by delivery truck. Both usually cost more per unit of heat than utility gas, so sealing and insulation pay back faster here than in a gas-heated town.
South Coventry and North Coventry: two building histories
South Coventry is the old center. Mills along Coventry Lake Brook made it a small industrial village in the 19th century, and South Coventry Village is listed on the National Register with its Victorian houses, the Bidwell Tavern of 1822 and a general store building from 1787. The area has over 100 historic buildings on the national register. Houses of that age are typically timber or balloon framed, often on stone foundations, with walls that were never insulated and wiring that may be older than anyone living in the house.
We work those houses from the inside and from the bottom up. The foundation and sill are sealed first, because air drawn in at the sill feeds every open wall bay above. The attic floor is sealed at the chimney and wall tops, then insulated. Walls are filled only where the cavities are reachable, the wiring is sound and the plaster can take it.
North Coventry is a different story. In the 18th century it was dairy and vegetable farms, and when many of those families left Connecticut’s rocky fields for the Ohio River valley, the land went back to second-growth forest. In the 1960s and 70s tract developments of raised ranches and split-levels were built on some of it, on one-acre lots, and after 1990 larger houses on two-acre lots followed. Those houses are younger and simpler, and their losses are the rim joists, garage ceilings, stepped attics and unsealed top plates described above.
We seal before we insulate
Insulation slows heat moving through a surface. It does nothing about air passing through a gap, and in a cape the biggest gap is the open floor under the upstairs bedrooms.
In a 1950s Coventry cape the order is: block and seal the open joist bays under the bedroom floor behind each knee wall; air seal the back of the knee walls, then insulate them; baffle the sloped ceilings so air can move from the eave to the top; seal the flat attic at the chimney, the plumbing stack and the top plates, then bring it to depth; and finish at the cellar sill and rim. Where the slopes are closed, the rafter bays are dense-packed or foamed from inside.
If a quote specifies a depth of insulation and never mentions air sealing, it is half a job.
What insulation costs in Coventry
Most of our projects run between $3,500 and $12,500. In a cape the number follows the length of knee wall, whether the sloped ceilings are open from above or closed, and the size of the flat attic. A split-level is priced on its attic sections, the open wall at each step, the rim joist and the garage ceiling. A pre-1940 South Coventry house costs more when the sill is stone and the walls need careful filling from inside.
Open cell foam runs R-3.9 to R-4.2 per inch. Closed cell runs R-6.9 to R-7.1 per inch and also acts as a vapor retarder, which is why it costs more and why it is right in some assemblies and unnecessary in others. All products are manufactured in the United States and meet applicable building code and safety standards. ENERGY STAR says sealing air leaks and adding insulation can save up to 10% on annual energy bills.
Insulation rebates in Coventry
Coventry’s electric company is Eversource, and Connecticut Natural Gas (CNG) is its gas company. Home Energy Solutions is open to customers of Eversource, United Illuminating, Connecticut Natural Gas and Southern Connecticut Gas, whatever fuel heats the house. With most Coventry homes on oil or propane, the Eversource electric account is how nearly everyone applies. Homes of one to four units qualify if they have not received the program’s services in the last six years, and a renter needs the landlord’s approval.
Home Energy Solutions starts with a visit from an authorized contractor, with a $40 copay effective 1 April 2026. Health and safety tests come first, which matters with a wood stove or older oil burner, then a blower-door test and, for forced hot air or central air conditioning, a duct test. Air sealing is provided at no cost for up to seven hours, and larger or older homes may need extra time at $10 an hour. There may be a waiting list, and the program is subject to available funding.
The 2026 Energize CT insulation rebate pays up to $2.00 per square foot or 75 percent of the total cost, whichever is less, up to a maximum of $10,000. Qualifying areas are attic floors, floored-over attics, walls, basement and garage ceilings and rim joists. Sloped ceilings and foam on the underside of a roof deck are not on the list, so ask the program before counting on a rebate for them. The insulation has to be recommended during a Home Energy Solutions visit, the project approved before installation, and the work performed by an approved contractor from the Energize CT Insulation Installers Network.
A two-person household on Energize CT’s 2026–2027 figures is Income Eligible at $63,703 or less, with no-cost service and up to 100 percent coverage of insulation costs; in Enhanced Incentives from $63,704 to $84,939, with a no-cost visit and up to $2.50 per square foot, on default limits that vary by zip code; and on the standard tier from $84,940. Households at or below 60 percent of state median income can also apply to the state’s Weatherization Assistance Program through the energy assistance intake. Parts of Coventry are designated environmental justice communities; the state’s map shows whether a specific address qualifies.
The insulation rebate is paid only when a contractor in the Energize CT Insulation Installers Network does the work, so ask any installer, including us, whether they are in that network before you sign. A Smart-E Loan from the Connecticut Green Bank can spread the cost with no money down and fixed payments, up to $50,000 for an owner-occupied home of one to four units, at 6.99% APR over 5, 7 or 10 years, 7.49% over 12, or 7.99% over 15 with lenders that offer it; projects go through the Green Bank’s participating contractors. No federal credit helps in 2026, since Section 25C covers nothing placed in service after 31 December 2025. Our Connecticut rebate guide covers the rest.
Code and climate in Coventry
61.7% of Coventry’s housing was built before 1980. Coventry sits in climate zone 5A, as every Connecticut town does.
When a family adds a room, the addition follows the 2022 Connecticut State Building Code if its application was filed on or after 1 October 2022, and so does a new house. That code is the 2021 IECC with Connecticut amendments. A new ceiling needs R-60, or R-49 at full depth over the top plate at the eaves, and a ceiling with too little room may use R-30 over a small area. Wood-frame walls need R-30 in the cavity, R-20 plus R-5 continuous, R-13 plus R-10 continuous, or R-20 continuous; floors R-30; basement walls R-15 continuous, R-19 cavity or R-13 cavity plus R-5 continuous; windows U-0.30. A new home must pass a blower-door test at 3.0 air changes per hour at 50 pascals on the prescriptive path and 5.0 at most, while the new envelope of an addition is exempt from that test and may be inspected visually. Connecticut’s next code, based on the 2024 IECC, has been adopted in draft; its effective date has been delayed.
Common questions about insulation in Coventry
Do you install insulation in Coventry, CT?
Yes, in North Coventry, South Coventry, around Coventry Lake and everywhere between. The largest share of the work is the 1940s and 50s cape and ranch, 28.8% of the housing, followed by North Coventry’s 1960s and 70s raised ranches and split-levels and the larger houses built after 1990. We also insulate the older houses of South Coventry, working from the stone foundation up and filling walls only where the wiring is sound.
How much does insulation cost in Coventry?
Most projects run $3,500 to $12,500. A cape is priced on its knee walls, its sloped ceilings, and whether they are open from above, plus the flat attic. A split-level is priced on the attic sections, the open wall at each level change, the rim joist and the garage ceiling. An older South Coventry house with a stone foundation and closed walls usually costs more. The price comes in writing after a free walk-through.
Are there insulation rebates in Coventry?
Yes. Coventry’s utilities are Eversource for electricity and Connecticut Natural Gas for gas, and because most homes burn oil or propane, most apply to Energize Connecticut’s Home Energy Solutions through Eversource. The visit is $40 on the standard tier. A cape’s flat attic floor is a listed rebate area, paying the lesser of $2.00 per square foot or 75 percent of cost up to $10,000, once the visit recommends it, the program approves it and an Insulation Installers Network contractor installs it. Check with the program about sloped ceilings. There is no federal tax credit in 2026.
The upstairs of our 1950s cape is freezing in winter and hot in summer. Why?
Because the upstairs is built inside the roof. The bedrooms are separated from unheated attic space by knee walls on both sides, a sloped ceiling and a small flat attic, and in most capes of that era the floor joists under the bedrooms run open into those cold triangles. Winter air slides under the floor; summer sun heats the roof boards just above the slopes. The fix is to block and seal the floor bays, seal and insulate the knee walls, baffle and fill the slopes, and seal the flat attic before adding depth.
Free estimate in Coventry
Our free estimate is a walk-through by our own people, kept apart from the Home Energy Solutions program; it earns no rebate. In a cape we open the knee wall hatches to see the joist bays and the backs of the walls, check the slopes and the flat attic, and look at the cellar sill. In a split-level we check each attic section, each step wall, the rim and the garage ceiling. A written scope and price follow, with no charge and no obligation.
Call 914-825-6824, 8am–8pm, seven days, or use the contact form. We work out of New Rochelle, NY, with a 100-plus in-house crew that never subcontracts.
Learn more
- Insulation contractors across Tolland County
- Mansfield and Storrs, Coventry’s neighbor to the east
- Tolland, bordering Coventry to the north
- Insulating older homes
- Crawl space insulation
- Open cell and closed cell spray foam