No local gas company serves Thompson, and utility gas heats 0.0% of its homes. Fuel oil heats 68.5%, wood 12.3%, electricity 12.8% and bottled gas 5.9%. In the town that fills Connecticut’s northeastern corner, bordered by Webster, Dudley and Douglas in Massachusetts and Burrillville in Rhode Island, heat comes by truck or by the cord, and a house that leaks spends more of both.
Thompson has 4,269 housing units. 76.8% are detached houses and 81.8% of occupied homes are owner-occupied, so nearly every job here is a household deciding for itself. The median unit dates from 1967. 27.6% of the stock, 1,180 homes, predates 1940; 15.0% is from the 1940s and 50s, 27.0% from the 1960s and 70s, 20.6% from the 1980s and 90s and 9.8% from 2000 on. 69.6% was standing before 1980.
On oil, the payback is counted in gallons: every hole sealed and every inch of attic added means fewer deliveries, winter after winter. On wood, it is counted in cords, and in the hours spent cutting, splitting and carrying them.
The houses we insulate in Thompson
Thompson is ten villages: East Thompson, Fabyan, Grosvenordale, Mechanicsville, North Grosvenordale, Quaddick, Quinebaug, Thompson Hill, West Thompson and Wilsonville. The North Grosvenordale Mill Historic District and the Thompson Hill Historic District are on the National Register. A house from before 1940 usually has empty walls, a cellar sill that has shrunk away from its foundation, and an attic floor with little or nothing on it. Many have a kitchen ell or shed added behind the main block, sometimes over a shallow crawl space instead of a cellar, and the joint between old and new is rarely sealed. We treat each part as its own assembly and check the wiring before filling any wall.
The 1950s added 550 homes, mostly capes and small ranches. The cape leaks at its knee walls, with open joist bays running under them to the eaves, and its sloped ceilings are packed against the roof boards with no room to vent. The ranch has a long, low attic of thin, settled fill over ceiling boxes and top plates nobody sealed.
The 1970s built 722 homes, the largest single decade, and the 1960s 430: raised ranches, split-levels and ranches. Their attics hold a few inches of fiberglass, flattened in places; the rim joist around a raised ranch’s lower level sits above grade with nothing on it; and the ceiling of the garage under a bedroom leaks cold air into the floor. The 508 homes of the 1980s and 371 of the 1990s have insulated walls and lose most of their heat overhead, at the hatch, the lights, the bath fans and the top plates.
The 270 attached units are townhouses and duplex halves, where the party wall at the attic line is the first thing to check and an association may own the roof. The 186 mobile homes, 4.4% of the stock, are covered in the questions below.
Wood heat in Thompson
12.3% of Thompson homes heat mainly with wood, and a wood-heated house has its own rules for insulation work.
The first is combustion air. A stove, a fireplace or an older boiler draws air from inside the house to burn and to push smoke up the chimney. Seal the house tightly and run the bath fans, the dryer and the kitchen hood at once, and the chimney can lose that fight: the stove drafts poorly, smoke spills when the door opens, or carbon monoxide builds. That is why Home Energy Solutions runs health and safety tests before any sealing, and why we look at every combustion appliance before we seal and again after. Working carbon monoxide alarms belong on every level either way.
The second is the chimney where it passes through the attic. The gap around it is often the biggest single hole in the ceiling, and it cannot be stuffed with foam or fiberglass. It is closed with sheet metal and high-temperature sealant, with insulation held back at the required clearance.
The third is where the heat goes. A stove heats the room it stands in, and in a leaky house the far bedrooms stay cold because the air that should carry warmth to them is leaving through the attic instead. Seal the attic plane and the rim and the stove’s heat stays in the house longer, so the far rooms warm up and the woodpile lasts.
We seal before we insulate
Insulation holds heat back only while the air around it stays put. A house with a hot stove and a leaky attic pulls outside air in at the bottom as fast as warm air escapes at the top.
In a 1970s Thompson raised ranch the work begins overhead: seal the top plates, the plumbing vent, the wire holes and ceiling boxes, close the chimney gap with metal and high-temperature sealant, weatherstrip the hatch and set baffles at the eaves. Then downstairs: seal and insulate the rim joist around the lower level and the garage ceiling under the bedroom. Then the attic floor is brought to depth.
If a quote specifies a depth of insulation and never mentions air sealing, it is half a job.
What insulation costs in Thompson
Most of our projects run between $3,500 and $12,500. A raised ranch or split-level is priced on attic area, the rim around the lower level and the garage ceiling. An older village house turns on its walls, its additions and the crawl spaces under them, and on how much chimney and wiring work has to be planned around. A 1980s or 90s house is often a smaller job, sealing the attic and topping it up.
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 Thompson
Eversource supplies Thompson’s electricity, and the town has no local gas company, so every household reaches Energize Connecticut through its Eversource electric account. Home Energy Solutions is open to customers of Eversource, United Illuminating, Connecticut Natural Gas and Southern Connecticut Gas, whatever fuel heats the house. It is designed for homes of one to four units; renters need the landlord’s approval, and a home that had the program’s services within six years must wait.
Home Energy Solutions costs a $40 copay on the standard tier, effective 1 April 2026. The program’s authorized contractor begins with health and safety tests, then runs a blower-door test to pinpoint drafts and air leaks and a duct test if there is forced hot air or central air conditioning. Air sealing is provided at no cost for up to seven hours, with $10 an hour for larger or older homes that need longer. There may be a waiting list, and the program is subject to available funding.
The 2026 Energize CT insulation rebate is worth up to $2.00 per square foot or 75 percent of the total cost, whichever is less, up to a maximum of $10,000. It covers attic floors, floored-over attics, walls, basement and garage ceilings and rim joists, but not foam on the underside of a roof deck, so ask the program before counting on a rebate there. An attic floor qualifies only if it starts at R-19 or less and ends at R-49 or more. The work must be recommended during a Home Energy Solutions visit, approved before it is installed, and installed by an approved contractor from the Energize CT Insulation Installers Network. Part of Thompson is designated an environmental justice community, where the incentive can reach $2.50 per square foot, up to $15,000; the state’s map shows whether a specific address qualifies.
For a one-person household, Energize CT’s 2026–2027 figures put Income Eligible at $48,714 or less, with no-cost service and up to 100 percent of insulation costs covered, and Enhanced Incentives at $48,715 to $64,953, with a no-cost visit and up to $2.50 per square foot; the middle range is a default that varies with zip code. At $64,954 and above the standard tier applies. Check your tier before paying a copay.
The rebate is paid only when a network installer does the work, so ask every installer you talk to, including us, whether they are in that network, and weigh the prices after any rebate. The Connecticut Green Bank’s Smart-E Loan finances insulation with no money down, up to $50,000, on an owner-occupied Connecticut home of one to four units: 6.99% APR over 5, 7 or 10 years, 7.49% over 12 and 7.99% over 15 where the lender offers it. It is arranged through the Green Bank’s participating contractors; ask whether your contractor participates. For smaller jobs, Eversource customers who own and occupy a one- to four-unit home can ask about the Energize CT Micro Loan from Capital for Change: up to $3,000 interest-free over 36 months, subject to credit approval, for improvements recommended through Home Energy Solutions and installed by an approved contractor. Insulation installed in 2026 earns no federal tax credit, because Section 25C ended for anything placed in service after 31 December 2025. Our Connecticut rebate guide covers the rest.
Code and climate in Thompson
69.6% of Thompson’s housing was built before 1980. The town lies on the 42nd parallel at the Massachusetts line, and like every Connecticut town it is in climate zone 5A.
New homes and additions with applications filed since 1 October 2022 are built to the 2022 Connecticut State Building Code, the 2021 IECC with state amendments. Ceilings must reach R-60, or R-49 carried at full, uncompressed depth over the wall top plate at the eaves. Wood-frame walls take R-30 in the cavity, R-20 cavity plus R-5 continuous, R-13 plus R-10 continuous, or R-20 continuous. Floors take 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 never test worse than 5.0. The next Connecticut code, built on the 2024 IECC, has been adopted in draft, but its effective date is delayed.
Common questions about insulation in Thompson
Do you install insulation in Thompson, CT?
Yes, in all ten villages, from North Grosvenordale and Grosvenordale to Thompson Hill, Quaddick, Wilsonville and East Thompson. Most of the work is detached houses: the 1,180 built before 1940, the capes and ranches of the 1950s, and the raised ranches and split-levels of the 1960s and 70s, with 722 homes from the 1970s alone. In wood-heated houses we check the stove, the chimney and the boiler before any sealing, and townhouse work may need the association’s approval first.
How much does insulation cost in Thompson?
Most projects run $3,500 to $12,500. A raised ranch is priced on its attic area, the rim around the lower level and the garage ceiling below the bedroom. An older village house depends on its walls, its additions and any crawl spaces, plus the chimney and wiring work that has to be planned around. A 1980s or 90s house is often a smaller job. The walk-through is free, and the scope and price come in writing.
Are there insulation rebates in Thompson?
Yes. With no local gas company, Thompson homes reach Energize Connecticut through Eversource, their electric company, whether they heat with oil, wood or bottled gas. The Home Energy Solutions visit is $40 on the standard tier. Insulation recommended at that visit, approved first and installed by an Energize CT Insulation Installers Network contractor can earn up to $2.00 per square foot or 75 percent of cost, whichever is less, to $10,000, and more in the part of town designated an environmental justice community. No federal tax credit applies in 2026.
We own a manufactured home in Thompson. Is there anything worth insulating?
Sometimes. A manufactured home has no attic to walk and no cellar; its floor insulation and heating ducts hang in a belly under the house, behind a thin bottom board. When that board tears, the insulation sags or falls out and the ducts lose heat to the outdoors. Repairing the bottom board, sealing the ducts and refilling the belly can help, and sealing around plumbing and wiring holes through the floor stops drafts. The roof cavity is harder to reach. Tell us the year and the heating system on the phone, and we will say whether a visit is worthwhile.
Free estimate in Thompson
Our free estimate is a walk-through of the house and has nothing to do with the Home Energy Solutions visit; it does not qualify anyone for a rebate. We start with how the house is heated, the stove, the boiler and the chimney, then go to the attic hatch, the top plates and the gap around the chimney. In a raised ranch we check the rim and the garage ceiling; in an older house, the walls, the ell and any crawl space. You get a written scope and a price, with no charge.
Call 914-825-6824, 8am–8pm, seven days a week, or use the contact form. We are based in New Rochelle, NY, and every job is done by our own 100-plus in-house crew; we never subcontract.
Learn more
- Insulation contractors across Windham County
- Putnam, Thompson’s neighbor to the south
- Woodstock, Connecticut, Thompson’s neighbor to the west
- Air sealing
- Attic insulation
- Crawl space insulation