The Home Insulators

Insulation Contractors in Franklin Township, NJ

Only 45.9% of Franklin Township’s 26,858 housing units are detached houses. That is the lowest detached share of any township in Somerset County, and it is the number that decides what an insulation contractor can and cannot do here. Another 20.3% is attached — 5,445 townhouses and duplex halves — 9.6% sits in two- to four-family buildings, and 10.4% is in buildings of twenty units or more. 68.3% of occupied units are owner-occupied.

The township is also young for its acreage. 25.4% of its housing has gone up since 2000, including 4,307 units in the 2000s alone, and 38.4% dates from the 1980s and 90s. The median unit was built in 1986. Only 3.1% predates 1940 and 36.2% predates 1980. Gas heats 77.5% of homes, electricity 17.4%, oil 2.8%.

So Franklin is really three markets on one map: the tract subdivisions and townhouse clusters of the last forty years, the older detached houses in the Somerset section next to New Brunswick, and a rural township — roughly three-quarters of the land — with farmhouses in the canal villages. Each one gets a different scope, and one part of Franklin is not our work at all.

The houses we insulate in Franklin Township

Franklin was a farming township that became a fast-growing suburb through the late twentieth and early twenty-first centuries, and the building record shows it: 6,403 units in the 1980s, 3,901 in the 1990s, 4,307 in the 2000s and 2,402 more in the 2010s. That is the subdivision belt through Franklin Park, Six Mile Run, Ten Mile Run and Franklin Center, and it is most of our work here.

In a 1980s or 90s colonial the walls are already insulated to R-11 or R-13 and the attic was built to R-19 or R-30. Neither is the job. The ceiling plane is: top plates never sealed, flue and plumbing chases open from the basement to the roof, recessed cans, an uninsulated hatch, bath fans dumping into the attic, and open joist bays under a bonus room over the garage. Where the air handler and its trunk sit in the vented attic, the duct leaks are usually the largest single loss in the house, and extra blown-in over the top of them changes nothing.

The post-2000 houses, 25.4% of the stock, are tighter but they brought two-story foyers, tray ceilings and cathedral slopes framed with no vent baffles, so the insulation in the slopes is packed against the sheathing and wind-washed at the eave. Those get baffled and filled properly, or closed-cell foam under the deck where the roof assembly calls for it.

The 5,445 attached units are a scope of their own. A townhouse loses heat in three places: the party wall, which is normally framed up into the attic and left open on both faces so your heated air feeds the next attic and outside air blows back along it; the garage ceiling, where the bedroom above sits on open joist bays; and the top-floor ceiling plane with its hatch and cans. End units add an exposed gable. Small footprint, small price, and usually the best return per dollar in the township.

Then the old Franklin. 3.1% predates 1940 and another 11.2% is 1940s and 50s, much of it in the canal villages along the Millstone River and the Delaware and Raritan Canal, dug in the 1830s and now a state park: Griggstown, Blackwells Mills, East Millstone, Weston, Middlebush, Kingston. Dutch settlers were building here long before that — the Van Wickle House beside the canal dates from 1722. Houses of that age are balloon framed with no fire blocking at the top plate, so a stud bay runs from cellar to attic as one open chimney, and they often still carry knob-and-tube wiring, which comes out before anything goes into a wall. The 1960s and 70s cohort, 21.9%, is ranch and split-level: settled loose-fill, wind-washed eaves, unsealed band joists between half-levels and a cold bedroom over the garage.

Apartments, condos and the part of Franklin we cannot help

10.4% of Franklin’s units are in buildings of twenty or more, including 1,911 in buildings of fifty-plus, and another 13.8% is in buildings of five to nineteen. Most of that is garden-apartment and mid-rise stock concentrated in the Somerset section next to New Brunswick, and it is not a retrofit market for the person living in it. The roof, the walls and the attic belong to a landlord or an association, and one unit’s ceiling is another unit’s floor. If you rent, the useful call is to the owner. If you own a condo in a building like that, the call is to your board and its engineer, because the envelope is a capital item for the whole building.

Two- to four-family buildings, 9.6% of the stock, are different: those we can do, but we scope them as one building rather than one apartment. The stair chase, the floor cavity between units and the roof are shared, so sealing half of the building does not work and there is no honest way to price half of it.

Everything else is ordinary work: the detached houses, the 5,445 townhouses and duplex halves, and the farmhouses in the rural three-quarters of the township. If you are not sure which side of that line your building sits on, describe it on the phone and we will tell you.

We seal before we insulate

Insulation slows heat moving through a surface. It does nothing about air moving through a gap. Put a foot of cellulose over an attic with open chases and recessed cans and you have a foot of cellulose sitting on top of a hole.

In a Franklin Park colonial the sequence runs: seal the top plates, chases and wire penetrations; cover or replace the cans; duct the bath fans outside; insulate the hatch; seal the air handler cabinet and every duct joint; baffle the tray and cathedral slopes; close the joist bays under the room over the garage; seal the basement rim. Insulation goes in last. In a townhouse it starts at the party wall in the attic. In a canal-village farmhouse it starts by blocking the balloon-framed stud bays at the top plate so the walls stop venting into the attic.

If a quote specifies a depth of insulation and never mentions air sealing, it is half a job.

What insulation costs in Franklin Township

Most of our projects run between $3,500 and $12,500. In a subdivision colonial the number moves with attic footprint, duct footage in the attic, how many cathedral and tray slopes need baffling and whether a bonus room sits over the garage. A townhouse usually sits toward the bottom of the range unless it is an end unit. A two- to four-family is priced as one building. An old house in Griggstown or East Millstone can reach the top, because balloon-framed cavities have to be blocked at every floor line and old wiring dealt with first. Our page on what spray foam insulation costs covers the foam 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. After air sealing and insulating, homeowners typically save 20% or more on heating and cooling.

Insulation rebates in Franklin Township

PSE&G serves Franklin Township for both electric and gas, so there is no question here about which utility runs the program. With 77.5% of homes heating with gas, the gas bill is what most of these projects are aimed at.

PSE&G Whole Home Energy Solutions pays up to $7,500 in rebates toward air sealing, insulation and the envelope work the assessment calls for, plus 0% on-bill repayment of up to $25,000, over 7 years for projects of $10,000 or less and 10 years above that or for income-qualified customers. It is written for owner-occupied homes of one to four units — the detached houses, townhouses and two- to four-family buildings, not the apartment buildings. It starts with a home energy assessment by a BPI-certified contractor participating in PSE&G’s program, and the contractor sets that fee. PSE&G does not publish per-measure amounts, so “up to $7,500” is as precise as anyone can be.

Separately, PSE&G’s Whole Home Energy Assessment is free — a walk-through that installs small items on the spot for any PSE&G residential customer in a home of fewer than five units, once a year. PSE&G Home Weatherization installs insulation, air sealing and duct sealing at no cost for households between 250% and 400% of the federal poverty level. New Jersey Comfort Partners does the same at or below 250% of the guidelines, $82,500 a year for a family of four, in buildings of 1 to 14 individually metered units.

The New Jersey IRA Home Energy Rebates have not launched. The state’s page says the programs are in development and not open for applications. The federal Section 25C tax credit ended for anything placed in service after 31 December 2025, so a 2026 job carries no federal insulation credit no matter what a mailer claims. The current picture is in our New York and New Jersey rebate guide.

Code and climate in Franklin Township

36.2% of Franklin went up before 1980, and that share predates New Jersey’s first statewide energy subcode of 1 January 1978 — nothing required insulation in those houses when they were framed. The bigger share, the 1980s and 90s tracts, met early energy codes that fall well short of what the state asks for today. Somerset County is climate zone 5A, the colder of New Jersey’s two zones.

New Jersey adopted the 2024 IECC on 17 August 2026. For new construction it sets R-49 ceilings — the 2021 edition it replaced called for R-60, and a complete permit application filed under the old code is still accepted until about 16 February 2027 — with walls at R-30 cavity or R-20 plus R-5 continuous, windows at U-0.28 for the 5A counties, and air leakage of 3.0 air changes per hour at 50 pascals.

Existing homes fall under New Jersey’s Rehabilitation Subcode. Insulating an attic does not require bringing the rest of the house to code and does not require a blower-door test. Blown-in or batt insulation installed against the interior finish is ordinary maintenance with no permit; spray foam and other foam plastic insulation need a permit, which we pull as part of the job. R-49 is what we design to.

Common questions about insulation in Franklin Township

Do you install insulation in Franklin Township, NJ?

Yes, in the houses. That means the detached homes of the subdivision belt through Franklin Park, Six Mile Run and Franklin Center, the 5,445 townhouses and duplex halves, the two- to four-family buildings, and the older farmhouses out in the canal villages. We do not work on garden apartments and mid-rise buildings, where the envelope belongs to a landlord or an association, and we will say which side of that line your building is on before anyone drives out.

How much does insulation cost in Franklin Township?

Most projects run $3,500 to $12,500. In a subdivision colonial the drivers are attic footprint, duct footage in the attic, the number of cathedral and tray slopes and a room over the garage. A townhouse normally sits at the low end unless it is an end unit with an exposed gable. A two- to four-family is priced as one building because the roof and stair chase are shared. An old balloon-framed house in the canal villages sits at the high end. Written scope and price after a free walk-through.

Are there insulation rebates in Franklin Township?

Yes. PSE&G is both the electric and the gas utility here, so one program covers the whole township. PSE&G Whole Home Energy Solutions pays up to $7,500 in rebates plus 0% on-bill repayment of up to $25,000, for owner-occupied homes of one to four units, starting with a home energy assessment. PSE&G’s separate Whole Home Energy Assessment walk-through is free once a year. Income-qualified households get the work at no cost through Comfort Partners or PSE&G Home Weatherization. New Jersey’s IRA rebates have not launched and the federal 25C credit ended after 31 December 2025.

We own a townhouse in Franklin Park. Can we insulate it without the association?

Usually yes, because the work is inside your own unit. Attic air sealing, party-wall sealing above your ceiling, the garage ceiling and blown-in over your own ceiling plane are all within your walls. What needs the association is anything touching the roof deck, the exterior siding or a shared mechanical chase. Send us your association’s rules and we will scope the job to what you control, and tell you plainly if the piece that matters most is on their side of the line.

Free energy audit in Franklin Township

We start in the attic: the ceiling plane, the top plates, the hatch, the cans, the bath fan runs and every foot of duct outside the insulation. In a townhouse we go straight to the party wall and the garage ceiling. In an older house near the canal we check for balloon-framed bays and old wiring before proposing anything, and in a two- to four-family we walk the whole building. Then a written scope and a price, with no charge and no obligation.

Call 914-825-6824 or use the form below. Open 8am–8pm, seven days. We work out of New Rochelle, NY with a 100-plus in-house crew, and we hold manufacturer installer certifications from the spray foam manufacturers we use.

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