The median Manorville home was built in 1993. The 1990s alone produced 1,751 of its 5,053 homes, 34.7% of the stock, the 1980s another 19.9%, and 25.8% has gone up since 2000; only 19.7% predates 1980. That changes what insulation means here: the walls are rarely empty, and the losses sit in the places a 1990s builder did not think about.
Manorville is a hamlet in the Town of Brookhaven, nicknamed “The Gateway to the Hamptons,” spread over 25.5 square miles in the center of Long Island with no access to the water. It sits at the western edge of, and partly within, the Long Island Central Pine Barrens; the land is heavily wooded, with wetlands in the north near the Peconic River, and much of the northeastern part lies in the Pine Barrens’ Core Preservation Area, where no further development is allowed.
Utility gas heats 52.5% of occupied homes, but fuel oil still heats 34.6%, electricity 10.1% and bottled gas 1.9%. 86.7% of occupied homes are owner-occupied. Detached houses are 70.7% of the stock, and the rest leans toward attached and small-building communities: 10.4% single-family attached and 7.1% in buildings of ten to nineteen units.
The houses we insulate in Manorville
The 1990s house is the core of the hamlet: a two-story colonial or a large ranch, framed with fiberglass batts in the walls and blown or batt insulation on the attic floor. It was built to the code of its year, and its walls are usually full. Its weak points are the tall wall of a two-story foyer or family room, the chase around a factory-built fireplace, cantilevered floors, recessed lights, and central air ductwork running through the attic. Those get their own section below.
The 1980s built 1,004 homes, 19.9% of the stock. Those include colonials like the 1990s houses, contemporaries with cathedral ceilings and clerestory windows, and ranches. A cathedral ceiling from that decade is usually a batt squeezed between rafters with little or no vent space above it, so it runs hot in summer and loses heat in winter, and the skylights set into it are often framed with gaps around the shaft.
Another 1,062 homes went up in the 2000s and 234 in the 2010s. Those houses were built to later codes and have full walls. Their losses are almost entirely overhead: an air handler and ducts in a vented attic, tray and vaulted ceilings with thin slopes, a bonus room over the garage, and bath fans that end in the attic instead of outdoors.
The oldest sizable group is the 1970s, 697 homes, mostly raised ranches and ranches. Those went up with thin attic insulation that has settled, and a raised ranch has a bare rim joist sitting on a foundation that stands partly above grade. On the slightly rolling ground the Ronkonkoma terminal moraine gives central Manorville, where a lot slopes, a basement wall can stand well out of the ground on one side, and that exposed concrete is part of the envelope too.
Oil matters even in a hamlet this new. A house on oil pays by the gallon for every leak, including the attic and duct leaks described below. The attached homes and small buildings are a separate case: in a townhouse or condo community the roof and attic may belong to an association, and we work on what the owner controls.
Two-story foyers, fireplace chases and the attic beside the wall
The 1990s house is well insulated on paper and leaky in a few specific places. They are the same places in house after house, and none of them shows up in a quick look across the attic floor.
The tall wall. Where a two-story foyer or family room meets a one-story section, the upper part of its wall faces an attic. Builders stapled batts to that wall with nothing to hold them on the attic side, and after thirty years they have often sagged or fallen away. Attic air then sits against the back of the drywall of the tallest room in the house. The fix is an air barrier on the attic face of that wall, sealed at the edges, with the insulation held tight behind it.
The fireplace chase. A factory-built or direct-vent gas fireplace was often set into a bump-out framed outside the main wall. The inside of that chase is frequently open to the attic at the top and to the outside or a crawl space at the bottom, with little or no insulation in its walls, so cold air falls down behind the firebox all winter. We cap the chase at the top with sheet metal or rigid board and fire-rated sealant, keeping the manufacturer’s clearances, seal the bottom, and insulate the chase walls.
Cantilevers and bays. A second floor or a bay that projects past the wall below has floor joists over outdoor air, closed only by a thin soffit panel. Those bays get opened, sealed at the wall line and filled.
The ducts. An air handler and supply ducts in a vented attic sit outside the insulation. Leaky joints push conditioned air into the attic in summer and winter alike. Sealing every joint and the air handler cabinet, then insulating the ducts or burying them in attic insulation, is often one of the biggest savings in a 1990s Manorville house.
We seal before we insulate
Insulation limits heat flow through a surface. Air leaks go straight past it, which is why a 1990s house with full walls can still have a cold foyer and a hot upstairs.
In a Manorville colonial the order is: in the attic, seal the top plates, the recessed light housings, the bath fans, the attic stair and the plumbing and flue penetrations; put an air barrier on the attic side of any two-story wall; cap and seal the fireplace chase; seal the ductwork and the air handler; then add insulation to depth over the whole floor. Then open and fill any cantilevers, and seal and insulate the rim joist in the basement.
If a quote specifies a depth of insulation and never mentions air sealing, it is half a job.
What insulation costs in Manorville
Most of our projects run between $3,500 and $12,500. In a 1990s colonial the number is driven by air sealing and ductwork more than by insulation depth: how much duct runs through the attic, whether the two-story walls and the fireplace chase need work, and how many cantilevers need opening. A 1970s raised ranch is priced on its attic, rim joist and garage ceiling. A townhouse depends on what the owner controls. For the foam side, 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 Manorville
Manorville homes buy electricity from PSEG Long Island. Gas comes from National Grid on many streets but not every one, and your bill shows which you have. PSEG Long Island homes are not eligible for NYSERDA’s Comfort Home program.
PSEG Long Island offers its own rebates, paid through its participating contractors after a free Whole House Energy Assessment with a thermal scan and a blower door test. For a market-rate single-family home it lists $2,500 for insulation, $1,000 for air sealing and $500 for duct sealing, with higher amounts for income-qualified homes and homes in state-designated disadvantaged communities. Those three line up with the 1990s house: insulation has to be installed with comprehensive, blower-door-assisted air sealing, and all ductwork in unconditioned space has to be duct sealed. Gas, oil, propane and electric heat all qualify. The list is written for single-family homes, and only PSEG Long Island’s participating contractors can deliver it, so check the list before you sign with anyone.
For owners thinking about heat pumps: PSEG Long Island’s window rebate, $4 per square foot for market-rate homes, applies only when the house gets a whole-house cold-climate air-source heat pump and, at a minimum, insulation and air sealing. The envelope comes first either way.
Income-eligible households can use NYSERDA’s EmPower+, for owners and renters of one- to four-family homes: air sealing and insulation at no cost up to $14,000 at or below $98,925 a year for a Suffolk family of four, or half the cost up to $7,000 below $131,900, through an EmPower+ contractor, plus up to $1,600 in federal HEAR funds. Long Island households should check eligibility on the MyEnergy portal; National Grid’s Long Island rebate program is not taking new applications. The federal Section 25C credit ended for work placed in service after 31 December 2025, and New York has no state tax credit for insulation. More in our New York and New Jersey rebate guide.
Code and climate in Manorville
19.7% of Manorville’s homes were built before 1980, and most of those are 1970s houses framed before New York’s first statewide energy code took effect on 1 January 1979. The rest were built after that code was in place, under the editions of their own years rather than today’s. Suffolk County is Climate Zone 4.
The current edition is the 2025 Energy Conservation Construction Code of New York State, in force since 31 December 2025. A new house must have R-49 in the ceiling; R-38 over the entire ceiling counts where the full uncompressed R-38 reaches over the wall top plate at the eaves. Floors need R-30, and basement and crawl space walls R-15 continuous, R-19, or R-13 plus R-5 continuous. Windows must be U-0.27 or better, and the finished house must test at no more than 3.0 air changes per hour at 50 pascals.
A house already built is not held to that. Unaltered parts of an existing home do not have to comply, and New York’s code does not require a blower door test when you insulate an existing home, though we may still recommend one in a 1990s house to find the leaks. Where an alteration opens a wall or roof cavity, it has to be insulated to full depth. ENERGY STAR puts the attic level for this zone at R-60 where there is no insulation, or R-49 where 3 to 4 inches are already in place.
Common questions about insulation in Manorville
Do you install insulation in Manorville, NY?
Yes. Most of our Manorville work is the 1990s house, 34.7% of the hamlet: attic air sealing, two-story walls, fireplace chases, cantilevers and attic ductwork. We also work on the 1980s contemporaries with cathedral ceilings, the houses built since 2000, the 1970s raised ranches, and townhouses where the owner controls the attic. We cover the whole hamlet, from the wooded north near the Pine Barrens to its southern streets.
How much does insulation cost in Manorville?
Most projects run $3,500 to $12,500. In a 1990s colonial the price follows the air sealing and ductwork more than the insulation depth: the length of duct in the attic, the two-story walls and fireplace chase, and any cantilevers to open. A 1970s raised ranch is priced on its attic, rim joist and garage ceiling. A townhouse depends on what the owner controls. The written scope and price come after a free walk-through.
Are there insulation rebates in Manorville?
Yes. Manorville is PSEG Long Island territory, and PSEG Long Island lists $2,500 for insulation, $1,000 for air sealing and $500 for duct sealing in market-rate single-family homes, more for income-qualified homes, paid through its participating contractors after a free Whole House Energy Assessment. Comfort Home is not available to PSEG Long Island homes. Income-eligible households can check EmPower+ on the MyEnergy portal. There is no federal 25C credit on a 2026 job and no New York state insulation credit.
Our Manorville house was built in the 1990s. Why would it need insulation work?
Because full walls are not the same as a sealed house. A 1990s house was almost never tested for air leakage when it was built, and its attic floor is usually crossed by leaky ductwork and cut through for lights and fans. The batts on the attic side of a two-story wall have often sagged, the fireplace chase is often open to the attic, and a cantilever may have little under it but a soffit panel. The usual job is sealing and duct work first, then topping up the attic, not adding insulation to the walls.
Free energy audit in Manorville
In a 1990s house we go into the attic first to look at the ducts, the air handler, the back of any two-story wall and the top of the fireplace chase, then check the cantilevers from outside, the rim joist in the basement and, where the lot slopes, the exposed foundation wall. In a townhouse we find out what you control before pricing anything. If the attic depth is fine and the problem is the ducts, we say so. The scope and the price follow in writing; the visit costs nothing and commits you to nothing.
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 Ridge
- Insulation in Riverhead
- Insulation in Shirley
- Air sealing for newer houses
- Attic insulation and duct sealing
- What happens during an energy audit