Half of East Setauket was built in two decades. 28.8% of the hamlet’s 3,949 homes date from the 1960s and 21.4% from the 1970s, together 50.2% of the stock, and the median home was built in 1972. The fuel is split down the middle: 45.4% of occupied homes heat with utility gas and 45.3% with fuel oil, with 5.8% on electricity and 2.0% on bottled gas.
It is a hamlet of owned houses. 76.6% of homes are detached and 9.4% are attached, 88.2% of occupied homes are owner-occupied, and the largest apartment share is the 5.4% in buildings of ten to nineteen units. 68.1% of the stock was built before 1980, and 9.9%, 391 homes, predates 1940.
East Setauket is a hamlet in the northwest part of the Town of Brookhaven. It was counted with Setauket as one place until 2020, and it sits between Setauket and Poquott to the north and northwest, Port Jefferson and Port Jefferson Station to the northeast and east, Terryville and South Setauket to the south, and Stony Brook and Stony Brook University to the west. The typical job is a 1960s or 70s house that has never had its air leaks sealed, whichever fuel heats it.
The houses we insulate in East Setauket
The 391 homes from before 1940 are the oldest layer, and we treat them as balloon-framed until we have seen otherwise: stud bays open from the cellar to the attic, and knob-and-tube wiring assumed until it is ruled out. Old wiring comes out before anything is blown into a wall. The 1940s added 95 homes and the 1950s 220, mostly capes and small ranches, and their weak points are familiar: knee walls with no air barrier behind them, and low attics of settled loose-fill.
The 1960s built 1,139 homes, the largest single decade: center-hall colonials, splits, high ranches and ranches. A colonial of that decade has batts in the walls, an attic of three to four inches that was never sealed underneath, an overhang where the second floor projects over the first, and a living-room fireplace with a masonry chimney running up through the middle or the end of the house. A split adds a lower level with a bare rim joist and a bedroom wing over it; a high ranch adds a garage under the bedrooms.
The 1970s built 844 more, many of them colonials and raised ranches with larger family rooms, sliding doors to the yard, and fireplaces of their own. By then the walls were insulated, but the attic hatch, the top plates and the chimney were left as they were. Almost none of them went up under a state energy code.
The 1980s added 481 homes and the 1990s 478: bigger colonials and contemporaries with two-story entries, vaulted family rooms, skylights and air handlers in the attic. Some of them have factory-built metal fireplaces inside framed chases, which matters below. The 372 attached homes we scope as whole buildings, since the party wall runs into a shared attic. The 214 units in buildings of ten to nineteen belong to associations that manage their envelopes, and the 121 mobile homes are a limited job: the floor can sometimes be sealed, the shallow roof rarely.
The fireplace and the chimney chase: a hole the size of a closet
Many 1960s and 70s houses were built with a fireplace, and it is often one of the largest single air leaks in the house. It leaks in three places, and only one of them is the damper.
The first is the damper itself: a cast-iron plate that was never airtight and has warped over fifty years of fires. Closed, it still lets warm room air up the flue all winter. A tight-fitting damper at the chimney top or a removable plug in an unused fireplace addresses it; that is work for a chimney professional, and we point it out when we see it.
The second is the gap around the masonry. Framing has to stay clear of a chimney, so builders left an open space between the brick and the floor and ceiling framing at every level. That gap can run all the way from the basement to the attic. We close it with sheet metal and high-temperature sealant, never with foam or insulation packed against the brick.
The third is the framed chase around a factory-built metal fireplace, common in the 1980s and 90s houses. The chase is a box of studs on the outside of the house, often with no insulation, no air barrier and no top plate where it meets the attic, and sometimes with a metal cap that lets wind straight down inside it. Cold air falls down the chase and chills the wall behind the fireplace. The fix is to close the top of the chase at the ceiling line, air seal it, and insulate its outside walls, keeping the clearances the fireplace maker requires around the flue.
The same thinking applies to the heating chimney. In an oil house the boiler vents up a masonry chimney that passes the attic floor with the same open gap. In a gas house the furnace and water heater may share that chimney. Either way, the gap gets sealed with the right material, and the appliances’ draft gets checked once the house is tighter.
We seal before we insulate
Insulation slows heat moving through a surface. It does nothing about air moving through a gap, and a two-story colonial with a chimney up its middle works like a chimney itself: air enters low and leaves high, through every opening at the top.
In a 1960s East Setauket colonial the order is: at the attic floor, the chimney gap, the top plates of every wall, the plumbing vent, the light boxes, the bath fan and the hatch; the joist bays at the second-floor overhang; the fireplace chase where there is one; then the basement rim joist and the sill. Only then do we add insulation, to depth on the attic floor and into the overhang and the rim.
If a quote specifies a depth of insulation and never mentions air sealing, it is half a job.
What insulation costs in East Setauket
Most of our projects run between $3,500 and $12,500. In a 1960s or 70s colonial the number moves with the attic area, the overhang, the length of the basement rim and whether a fireplace chase needs to be opened, closed and insulated. A 1990s house with a vaulted room, skylights and ducts in the attic is priced on those, not the walls. A pre-1940 house with balloon-framed walls to block and fill sits higher. For the foam side of the price, see what spray foam costs.
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 East Setauket
PSEG Long Island is East Setauket’s electric company. National Grid supplies gas, which is available on many streets but not every one; the bill settles whether yours is among them. Since the electricity is PSEG Long Island’s, NYSERDA’s Comfort Home program is not an option for East Setauket homes.
The utility program here is PSEG Long Island’s. A free Whole House Energy Assessment comes first, including a check of insulation and drafts, a thermal scan and a blower door test. For market-rate single-family homes PSEG Long Island then 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. Gas and oil houses are equally eligible, as are propane and electric. The insulation must be installed with blower-door-assisted air sealing, and payment goes through PSEG Long Island’s participating contractors, so confirm that with whoever quotes the work. The list is written for single-family homes, so an attached-home owner should check with PSEG Long Island.
National Grid’s Long Island insulation rebate program is not taking new applications; income-eligible households now go through EmPower+. For owners and renters of one- to four-family homes under Suffolk County’s limits, NYSERDA’s EmPower+ program can pay for air sealing and insulation at no cost up to $14,000 for lower-income households (at or below $98,925 for a household of four) or half the cost up to $7,000 for moderate-income households (below $131,900 for four), through an EmPower+ contractor. Long Island households should check eligibility on the MyEnergy portal. NYSERDA’s Green Jobs–Green New York loans run $1,500 to $25,000 over 5, 10 or 15 years, unsecured.
The federal insulation tax credit (Section 25C) ended for work placed in service after 31 December 2025, so a 2026 job has no federal credit, and New York has no state tax credit for insulation. Our New York and New Jersey rebate guide has the details.
Code and climate in East Setauket
68.1% of East Setauket’s homes were built before 1980. New York’s first statewide energy code took effect on 1 January 1979, after the hamlet’s 1960s and nearly all of its 1970s houses were already standing. Suffolk County is Climate Zone 4.
The 2025 Energy Conservation Construction Code of New York State, in force since 31 December 2025, sets the bar for new homes: R-49 ceilings, or R-38 across the entire ceiling where the uncompressed R-38 extends at full height over the wall top plate at the eaves; R-30 floors; basement and crawl space walls at R-15 continuous, R-19, or R-13 plus R-5 continuous; windows at U-0.27 and skylights at U-0.50; and air leakage no greater than 3.0 air changes per hour at 50 pascals.
Those numbers govern new construction, not a house being improved. Unaltered portions of an existing house do not have to comply, and New York’s code does not require a blower door test when you insulate an existing home. If an alteration exposes roof or wall cavities, such as opening a fireplace chase or a vaulted ceiling, those cavities must be insulated to full depth. ENERGY STAR recommends R-60 for an uninsulated attic in this zone and R-49 where 3 to 4 inches are already in place.
Common questions about insulation in East Setauket
Do you install insulation in East Setauket, NY?
Yes. Most of our East Setauket work is in the 1960s and 70s houses that make up 50.2% of the hamlet: colonials, splits and raised ranches with unsealed attics, second-floor overhangs, bare basement rims and fireplaces whose chimney gaps were never closed. We also work in the 1980s and 90s colonials and contemporaries with chases, vaulted rooms and attic ducts, the pre-1940 houses with balloon-framed walls, and attached homes scoped as whole buildings.
How much does insulation cost in East Setauket?
Most projects run $3,500 to $12,500. In a 1960s or 70s colonial the drivers are the attic area, the overhang, the length of basement rim and whether a fireplace chase needs work. A 1990s house with a vaulted room, skylights and ducts in the attic is priced on those. A pre-1940 house with balloon-framed walls sits higher. We give a written scope and price after a free walk-through, and gas or oil does not change what we recommend.
Are there insulation rebates in East Setauket?
Yes. East Setauket buys electricity from PSEG Long Island, which lists a $2,500 insulation rebate and a $1,000 air-sealing rebate for market-rate single-family homes, with more for income-qualified homes, paid through its participating contractors after a free Whole House Energy Assessment. Gas-heated and oil-heated houses both qualify. Comfort Home is not available to PSEG Long Island customers. Income-eligible households can apply to EmPower+. The federal 25C credit ended for work placed in service after 31 December 2025, and New York has no state tax credit for insulation.
Our East Setauket house heats with gas, and our neighbor’s heats with oil. Should the insulation work be different?
The plan is the same: seal the attic floor, the chimney gap, the overhang and the rim, then insulate to depth. Two things differ. An oil house saves in fewer deliveries at a price that moves, and its boiler chimney gets a draft check after sealing. A gas house saves on the National Grid bill, and an older water heater venting up a chimney needs the same check, because a tighter house can pull air back down a weak flue. Both fuels are eligible for PSEG Long Island’s rebates.
Free energy audit in East Setauket
We start in the attic: the chimney gap, the top plates, the hatch, the depth and condition of what is already there, and any ducts. We look at the fireplace, the damper and, in a newer house, the chase from inside and out. Then the second-floor overhang, the basement rim and sill, and how the boiler, furnace and water heater vent. If the attic and the chimney gap are the whole job, we say so. Then a written scope and a price. No charge, no obligation.
Call 914-825-6824 or write to us through our contact page. 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 Stony Brook
- Insulation in Centereach
- Insulation in Selden
- Air sealing
- Attic insulation
- Open cell and closed cell spray foam compared