The Home Insulators

Insulation Contractors in Collingswood, NJ

Only 38.0% of Collingswood’s 7,009 housing units are detached houses. The rest is the form this borough was built in: 14.9% attached twins and row halves, 15.7% in two- to four-family buildings, and 23.8% in buildings of twenty or more, 19.0% of them in buildings of fifty-plus. 54.4% of occupied units are owner-occupied, the lowest owner share of any Camden County town we cover.

It is also old. The median unit dates from 1943, 46.5% predates 1940 and 90.7% of the borough was standing before 1980. Collingswood was laid out as a rail suburb five miles east of Center City Philadelphia and built out early, and what that leaves us is a town of shared walls, shared stairs and attics that two households have to agree about.

The houses we insulate in Collingswood

The eras: 46.5% before 1940, 26.2% in the 1940s and 50s, 18.0% in the 1960s and 70s, 5.7% in the 1980s and 90s and 3.6% since 2000. Quakers settled along Newton Creek and the Cooper River in the late 17th century and much of the borough was Collings family farmland into the 19th; it split from Haddon Township as a borough in 1888, the same year Edward Collings Knight gave the land that became Knight Park. The Cooper River is still the northern boundary and Newton Creek the southern one, and Haddon Avenue is still the spine, with the PATCO Speedline running above it on elevated track.

The pre-1940 half is where our work is. The twin is the signature house: two dwellings under one roof, sharing a party wall that in a great many of them stops at the ceiling joists instead of continuing to the roof deck. When it does, the two attics are one attic, and half of a heating system is warming the neighbor’s roof. The side walls are usually balloon-framed, meaning stud bays that run from sill to attic with no firestop, so cellar air travels up inside the wall and unloads overhead. Add plaster and lath, knob-and-tube that has to be cleared before any cavity is filled, and a deep front porch roof tucked under the second-floor wall, and you have the four problems we find over and over here. Anyone quoting a twin without going into the attic to look at the party wall has not looked at the house.

Then the conversions. A large pre-war house cut into flats gives us the 15.7% in two- to four-family buildings: a stair chase running the full height of the building, a floor cavity between the units that is open at the perimeter, often one heating plant in the cellar serving everything, and a low-slope roof over the top unit. We scope those as one building, because sealing the ground-floor apartment and leaving the stair and the floor cavity open changes very little. The oldest houses in the borough are another matter entirely — the Stokes-Lees mansion dates to 1707 and is among the oldest in Camden County, and the Collings-Knight homestead is 1820s work. Solid masonry has no cavity to fill, and those houses get the attic, the cellar and any later frame wing instead.

The 26.2% built in the 1940s and 50s is capes and small colonials on the later streets, failing at the knee wall and the open eave. The 18.0% from the 1960s and 70s adds ranchers and splits with settled attic fill. And 6.3% of occupied units still burn fuel oil, above the county’s 4.6%, which matters both for payback and for which program will take the job. Cellars near the river and the creek run damp, so the useful surface down there is the rim joist and the floor deck rather than the foundation wall.

Twins, flats and who is allowed to say yes

Two things decide whether a Collingswood project can happen: what the building is, and who owns it.

On the building: a twin and a two-family have to be treated as one envelope. The party wall gets closed off at the roof deck before anything is blown, because a shared attic leaks in both directions and one owner cannot fix half of it. Where the wall is masonry and already runs to the underside of the roof, the job gets simpler and cheaper, and we will tell you that on the walk-through. Where the two halves have different owners, we scope one side and note plainly what will still be crossing the line afterward.

On ownership: the Whole Home rebate program is written for one- to four-unit homes the owner lives in. In a borough where 54.4% of occupied units are owner-occupied and 23.8% sit in buildings of twenty or more, that rules out a lot of the housing stock. If you live in your twin or in one unit of your two- or three-family, you are inside the program. If you are a landlord living elsewhere, or you rent an apartment in one of the big buildings, the rebate is not available for that building and the envelope decisions are not yours to make anyway. We would rather say that at the start than after a visit.

We seal before we insulate

Insulation slows heat moving through a surface. It does nothing about air moving through a gap. Insulate one side of a shared Collingswood attic and you have paid to heat the party wall.

In a twin the sequence is: close the party wall from the top of the ceiling joists to the roof deck, plug the tops of the balloon-framed stud bays at the plate, seal the flue and plumbing chases, the attic hatch, the recessed lights and the bath fans, then baffle any slope that has to hold insulation, then insulate the attic plane. The porch roof cavity under the second-floor wall gets checked and sealed while the crew is in there. The cellar rim is last. In a converted two- or three-family, the stair chase and the floor cavity between units come before any of it.

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

What insulation costs in Collingswood

Most of our projects run between $3,500 and $12,500. A twin is priced on the attic area, the length of party wall to close, the number of stud bays to plug and whether knob-and-tube has to come out first. A converted flat building is priced as one building, with the stair chase and the inter-floor cavity in the scope. A post-war cape is usually a smaller job: knee walls, blocked eave, the flat above and the rim. Solid-masonry houses get no wall line, because there is no cavity to fill. The foam side of the price is broken down in our guide to what spray foam insulation 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. After air sealing and insulating, homeowners typically save 20% or more on heating and cooling.

Insulation rebates in Collingswood

Collingswood is PSE&G for both electric and gas. 72.7% of occupied units heat with gas, 18.5% with electricity, 6.3% with fuel oil and 0.7% with bottled or LP gas.

PSE&G Whole Home Energy Solutions is the program that matters, and its eligibility rule matters as much as its money: one- to four-unit buildings, owner-occupied, which takes in the twins and the smaller conversions and leaves out the large apartment houses. Inside those limits a project can earn up to $7,500 in rebates covering air sealing, insulation and the rest of the envelope scope, with the balance repayable at 0% on the bill up to $25,000 — seven years at $10,000 or under, ten above that or for income-qualified customers. It opens with a home energy assessment by a BPI-certified contractor enrolled with PSE&G, at a fee the contractor sets. Nothing is published measure by measure, so the ceiling figure is where the honest answer stops.

The free item sits beside that, under an almost identical name: PSE&G’s Whole Home Energy Assessment, a no-cost walk-through with small measures fitted on the spot, available to any PSE&G residential gas or electric customer in a building under five units. Then the income-qualified track, which fits a good deal of this borough. PSE&G Home Weatherization installs insulation, air sealing and duct sealing at no charge between 250% and 400% of the federal poverty level, or in a low- or moderate-income tract, or on NJ SHARES. New Jersey Comfort Partners reaches households at or below 250% of the federal poverty guidelines, $82,500 a year for a family of four, and serves buildings of 1 to 14 individually metered units — a description that fits the converted flats here almost exactly. Oil, propane and kerosene households go to the state weatherization office instead, which is where the 6.3% on oil would land.

Ignore two things you may have been told. The IRA Home Energy Rebates are still not open in New Jersey; the state calls them in development and closed to applications. And the federal Section 25C credit expired for work placed in service after 31 December 2025, so a 2026 job earns nothing federally, whatever an advertisement claims. The current list is in our New York and New Jersey rebate guide.

Code and climate in Collingswood

90.7% of Collingswood was built before 1980, and therefore before New Jersey’s first statewide energy subcode of 1 January 1978. Nearly half the borough was up before 1940, when a party wall stopping at the ceiling was normal practice and nobody was required to insulate anything. Camden County is climate zone 4A.

The state has been on the 2024 IECC since 17 August 2026. Its new-construction numbers for this zone: a R-49 ceiling, where the 2021 edition wanted R-60; walls at R-30 in the cavity or R-20 plus R-5 of continuous insulation; U-0.30 glazing; and a blower-door result of 3.0 air changes per hour at 50 pascals or better. Applications completed under the older edition are accepted for about six months yet, to roughly 16 February 2027. R-49 is also the ceiling target we design to on a retrofit.

A building that already exists is covered by New Jersey’s Rehabilitation Subcode instead. Insulating an attic there forces no upgrade to the rest of the building and calls for no blower-door test. Blown-in and batt insulation set against the interior finish is ordinary maintenance and takes no permit; spray foam and other foam plastic insulation do take one, which we pull with the job.

Common questions about insulation in Collingswood

Do you install insulation in Collingswood, NJ?

Yes. Most of our work here is the pre-1940 half of the borough: twins with an open party wall, balloon-framed side walls and knob-and-tube, plus the large old houses converted into two, three and four units. We also do the post-war capes and the 1960s and 70s ranchers. We do not work in the big apartment buildings that hold 19.0% of the units, where there is no attic to reach and the envelope belongs to the building.

How much does insulation cost in Collingswood?

Most projects run $3,500 to $12,500. A twin is priced on attic area, the feet of party wall to close off at the roof deck, the number of stud bays to plug at the top plate, and whether old wiring has to be removed first. A converted flat building is quoted as one building, including the stair chase and the floor cavity between units. A cape is usually smaller: knee walls, eave blocking, the flat and the rim. You get a written scope and price after a free walk-through.

Are there insulation rebates in Collingswood?

Yes, for one- to four-unit homes the owner lives in. Collingswood is PSE&G for gas and electric, and PSE&G Whole Home Energy Solutions pays up to $7,500 in rebates plus 0% on-bill repayment of up to $25,000, starting with an assessment by a BPI-certified contractor in the program. PSE&G’s separate Whole Home Energy Assessment walk-through is free once a year. Comfort Partners covers work at no cost for income-qualified households. New Jersey’s IRA rebates have not launched and the 25C credit ended after 31 December 2025.

We own one half of a twin. Can our side be insulated on its own?

Usually yes, but the party wall has to be part of the scope. If the wall stops at the ceiling joists, your attic and your neighbor’s are one space, and insulating your side without closing that wall to the roof deck leaves the leak in place. We can close it from your attic in most cases, so no work is needed on the other side of the house. If the framing does not allow it, we will tell you what will still cross the line and what your side is realistically worth doing.

Free energy audit in Collingswood

We go into the attic first and look at the party wall, the top plates and the chases, then check the slopes, the hatch and the bath fan terminations. In a converted building we look at the stair chase and the floor cavity between units. Then the porch roof, then the cellar for the rim joist and the condition of the walls. Then a written scope and a price. No charge, no obligation, and if the attic is sound and the money belongs in the walls, we say so.

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 that we never subcontract, and we hold manufacturer installer certifications from the spray foam manufacturers we use.

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