Elwood built 1,503 homes in the 1960s and 1,263 in the 1950s, 38.9% and 32.7% of its 3,866 homes. Most of the hamlet went up in those two decades on what had been farmland, the median home dates from 1963, and 84.8% of the stock predates 1980. Only 2.7% is older than 1940, and 9.2% has been built since 2000.
Elwood is a hamlet in the Town of Huntington, called “The Heart of Huntington” for its place in the middle of the town. It was once known as Northern Dix Hills, and it has had no post office of its own since 1902, so Elwood homes use East Northport, Huntington or Greenlawn mailing addresses. 90.6% of its homes are detached houses, and 96.6% of occupied homes are owner-occupied.
Utility gas heats 57.5% of occupied homes and fuel oil 38.6%, with electricity at 2.2%. National Grid gas reaches most Elwood streets but not all of them. For the homes still on oil, every gallon of heat a 1950s attic lets escape comes back on the next delivery.
The houses we insulate in Elwood
Elwood was farm country for most of its history. Farmers came for the level land and Long Island’s rich soil, and the first settlers arrived in the mid to late 1800s. Today Jericho Turnpike, Elwood Road, Cuba Hill Road, Clay Pitts Road and Burr Road cross the hamlet, and most of what lines and backs onto them dates from the 1950s and 60s.
The 1950s ranch has one long attic over every room. Its few inches of original insulation have settled, and every electrician and cable installer since has pushed a path through them. The top plates, the light boxes, the plumbing stack and the flue chase were never sealed, and the rim joist sits bare on top of the basement or crawl space wall. The cape of the same years has its upstairs behind knee walls, with the floor bays under them open to the eave and slopes packed with a thin batt against the roof deck. Many Elwood capes have a dormer added since, with its own cheek walls and a short attic that is rarely insulated as well as the rest.
The 1960s brought the largest share, with splits and high ranches alongside more ranches. A split puts its bedrooms over a garage and a lower level, with a wall facing the attic of the lower wing that was framed like an interior partition and never insulated like an outside wall. A high ranch has its garage and family room half in the ground, a long rim joist exposed above the foundation, and a bedroom floor over the garage.
Elwood’s newer stock is small: 272 homes from the 1970s, 76 from the 1980s, 154 from the 1990s and 214 from the 2010s. The newest houses have full walls; their losses are at the attic hatch, the ducts and the bath fans.
With 38.6% of homes on oil, an oil-heated ranch with an unsealed attic sees the change in its deliveries; a gas-heated house sees it on the bill. Either way, the attic plane and the rim are where the money leaves.
Garages that became family rooms: the slab, the old door opening and the ceiling
A 1950s or 60s Elwood house was sized for its first family. One common way to find more room without building up is to turn the attached garage into a den, a playroom, an office or a bedroom. The conversion usually looks finished. It is also, very often, the coldest room in the house, for three reasons.
The floor is still the garage slab. Concrete poured on the ground, with no insulation under it and often no vapor barrier, frequently a step below the rest of the house. Carpet over it stays cold, and a wood floor laid right on it can cup from ground moisture. Where headroom allows, the fix is rigid foam board laid over the slab and taped, with a new plywood subfloor on top, which also brings the floor closer to the level of the house. Where it does not, sealing and insulating the slab edge and the bottom of each outside wall matters most.
The walls were never meant to be outside walls of a living space. The old overhead door opening was framed in with a short wall, sometimes holding a window, often with little in the cavity, and its bottom plate sits on a slab edge that was built to shed rain, not stop air. The other garage walls may have been insulated only where drywall happened to go up. Those walls get drilled or opened, filled, and sealed at the bottom plate.
The ceiling hides a separate attic. The space over a garage is often its own vented attic, cold in winter and hot in summer, with the drywall below insulated lightly or not at all, and it frequently connects to the main attic over the house. It needs what any attic needs: seal the ceiling plane, close any opening into the house attic, then insulate to depth. A converted garage heated by one extended duct or a short baseboard run, facing three outside walls and a slab, depends on that envelope more than any other room does.
We seal before we insulate
Insulation slows heat conducted through a ceiling, wall or floor. Air slipping through a gap takes heat with it anyway, and batts and loose-fill do nothing to stop it.
In an Elwood ranch the work starts in the attic: pull back the insulation at the edges, seal the top plates, wire holes, light boxes and plumbing stack, close the gap around the flue with sheet metal and high-temperature sealant, weatherstrip the hatch, set baffles at the eaves, then blow in new insulation to depth. Below, seal the sill and insulate the rim joist all the way around. In a split, the wall facing the lower attic gets an air barrier on its attic side before anything else, and in a converted garage the bottom plates and the connection to the house attic come first.
If a quote specifies a depth of insulation and never mentions air sealing, it is half a job.
What insulation costs in Elwood
Most of our projects run between $3,500 and $12,500. A 1950s ranch with one attic and a rim joist sits toward the lower end. A split or high ranch with its attic, rim, garage ceiling and the wall facing the lower attic is mid-range. A cape with a dormer and knee walls, or a house with a converted garage whose slab, walls and ceiling all need work, runs toward the top. Our garage insulation guide covers the garage side.
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 Elwood
Elwood’s electric company is PSEG Long Island, and its gas company, on the streets with gas, is National Grid. The electric company sets which rebates apply, so an Elwood home looks to PSEG Long Island.
PSEG Long Island offers a free Whole House Energy Assessment, which includes a check of insulation and drafts, a thermal scan to find hidden heat loss and a blower door test. For market-rate single-family homes, it lists a $2,500 insulation rebate and a $1,000 air-sealing rebate, plus $500 for duct sealing, with higher amounts for income-qualified homes and homes in state-designated disadvantaged communities. Oil-heated and gas-heated homes are both eligible. Insulation has to be installed together with comprehensive, blower-door-assisted air sealing, and only PSEG Long Island’s participating contractors can deliver the rebate, so check any contractor against its list first.
National Grid’s Long Island insulation rebate program is not taking new applications, and income-eligible households now use NYSERDA’s EmPower+, which covers air sealing and insulation for owners and renters of one- to four-family homes through an EmPower+ contractor: at no cost up to $14,000 for lower-income households, or half the cost up to $7,000 for moderate-income households. In Suffolk, a one-person household is in the lower tier at or below $69,263 and the moderate tier below $92,350. Long Island households should check eligibility on the MyEnergy portal.
NYSERDA’s Green Jobs–Green New York program offers unsecured loans of $1,500 to $25,000 over 5, 10 or 15 years; they are loans, not rebates, and are paid back. The federal insulation tax credit (Section 25C) ended for work placed in service after 31 December 2025, so there is none on a 2026 job, and New York has no state tax credit for insulation. The full rundown is in our New York and New Jersey rebate guide.
Code and climate in Elwood
84.8% of Elwood’s homes were built before 1980. New York’s first statewide energy code did not take effect until 1 January 1979, long after the hamlet’s ranches, capes and splits were finished. Suffolk County is Climate Zone 4.
The current 2025 Energy Conservation Construction Code of New York State, in force since 31 December 2025, sets new-home ceilings at R-49, with R-38 accepted over the whole ceiling where it reaches full uncompressed height above the wall top plate at the eaves. Floors are R-30; basement and crawl space walls R-15 continuous, R-19, or R-13 plus R-5 continuous; windows U-0.27; and air leakage no more than 3.0 air changes per hour at 50 pascals.
For an existing house, the unaltered parts need not comply, and New York’s code does not require a blower door test when you insulate an existing home. New envelope assemblies built as part of an alteration must meet current requirements, existing insulation may not be reduced, and cavities an alteration exposes get filled to full depth, which is worth knowing before a garage conversion closes its walls. ENERGY STAR recommends R-60 for an uninsulated attic and R-49 where 3 to 4 inches are already there.
Common questions about insulation in Elwood
Do you install insulation in Elwood, NY?
Yes, across Elwood, whether your address reads East Northport, Huntington or Greenlawn. Most of the work is the 1950s ranches and capes and the 1960s splits and high ranches: attics, rim joists, knee walls, garage ceilings and the wall facing a lower attic. We also insulate converted garages, dormers and the newer houses with attic, duct and hatch problems. If you are unsure whether your street is in Elwood, give us the address when you call.
How much does insulation cost in Elwood?
Most projects run $3,500 to $12,500. A 1950s ranch with one attic and a rim joist is toward the low end. A split or high ranch with its attic, rim, garage ceiling and lower-attic wall is mid-range. A cape with a dormer and knee walls, or a converted garage that needs its slab, walls and ceiling done, costs more. A written scope and price follow a free walk-through.
Are there insulation rebates in Elwood?
Yes. PSEG Long Island, Elwood’s electric company, lists a $2,500 insulation rebate and a $1,000 air-sealing rebate for market-rate single-family homes, with higher amounts for income-qualified homes, paid through its participating contractors after a free Whole House Energy Assessment. Gas and oil heat both qualify. National Grid’s Long Island program is closed to new applications, and income-eligible owners and renters can apply to EmPower+. The federal 25C credit ended for work placed in service after 31 December 2025, and New York has no state insulation credit.
Our garage is still a garage. Why is the bedroom beside it in our Elwood house so cold?
Because the wall between them is often the weakest outside wall in the house. The garage is unheated, and that shared wall may have thin insulation or none, with gaps where it meets the slab and the ceiling. The attic over the garage frequently opens into the attic over the house, so cold air moves across. The fix is to fill the shared wall from the garage side, seal its bottom plate, close the opening between the two attics, and weatherstrip the door into the house. If a room sits over the garage too, its ceiling gets sealed and insulated.
Free energy audit in Elwood
In a ranch or cape we start in the attic, measure what is left of the original insulation and find the open top plates and the flue gap, then check the knee walls and any dormer. In a split or high ranch we look at the wall facing the lower attic and the garage ceiling. In a converted garage we check the slab, the framed-in door opening and the attic above. Then the basement rim and the burner’s air supply. You get a written scope and price, with no charge and no obligation.
Call 914-825-6824 or use our contact form. Open 8am–8pm, seven days. We work out of New Rochelle, NY with a 100-plus in-house crew that never subcontracts.
Learn more
- Insulation contractors across Suffolk County
- Insulation in Greenlawn
- Insulation in East Northport
- Insulation in Dix Hills
- Attic insulation
- Wall insulation
- Insulating older homes