North Castle is two housing markets under one town government. The median
North Castle house was built in 1971. The median house in
Armonk, inside this town, was
built in 1989. The town’s older stock — the 1960s houses
and what predates them — sits outside the Armonk core, in Banksville,
North White Plains and the roads between.
The houses we insulate in North Castle
North Castle is 82.6% detached, 88.0% counting attached, and
85.7% owner-occupied. The largest decade is the 1960s
at 19.7%, then the 1990s at 15.2%, the 1950s at 12.4%, the 1970s at
11.7%. That 1990s figure is worth pulling apart: 26.3% of the
town went up after 1990, but 48% of Armonk did. Take Armonk out and what is left
is a mid-century town.
So the house we walk into most often here is a 1960s colonial, ranch or split
with R-11 to R-13 in the walls and about R-19 over the ceiling.
That is not a defect and we do not sell it as one. It met the standard of its
day and passed inspection. It is now roughly a third of what a new house in this
climate zone would be built to, and the difference was never added.
What we find above the ceiling is consistent. Loose fill settled to four or
five inches and wind-washed to nothing over the top plates at the eaves, with no
baffles behind it. An open masonry chimney chase from basement to roof. Unsealed
top plates above the second-floor partitions, a bare hatch, a bath fan dumping
into the soffit. Below, a rim joist nobody has touched since 1965 and, where
there is a room over the garage, a garage ceiling with nothing in it.
The oil tank changes the arithmetic. 58.6% of North Castle
heats with fuel oil against 26.3% on utility gas, and outside
the hamlet centers many of these roads have no gas main to connect to. The tank,
the burner and the distribution lines all sit in that same uninsulated basement,
and every foot of open rim around them is heat leaving before it reaches a
room.
The work is ordinary and it holds up. Baffle and block at the eaves, seal the
chase, the top plates, the hatch and the fan penetrations, bring the attic floor
to depth, insulate the rim joist, close the garage ceiling. Walls come
after.
We seal before we insulate
Insulation slows heat moving through a surface. It does nothing about air
moving through a gap. Pack a leaky attic with cellulose and you have a leaky
attic with cellulose in it — the air still moves, it just moves through
something softer.
On a 1960s North Castle house that is not theory. The existing R-19 is
already thin at the eaves because outdoor air has washed through it for sixty
winters, and adding a foot of material over an open chimney chase gives that air
a longer path, not a shorter one. Close the holes, baffle the eaves. Then we
insulate.
If a quote gives you a depth and never mentions air sealing, it is half a
job.
What insulation costs in North Castle
Most of our projects run between $3,500 and $12,500. A 1960s
ranch attic with a chase to close and a rim joist to seal sits near the bottom.
A larger house with several roof planes, a room over the garage and settled
material to clear first sits higher, and that is labor rather than
material.
ENERGY STAR says sealing air leaks and adding insulation can save up to 10% on annual energy bills. On oil that is a number you count yourself, in deliveries
per winter, without waiting for a utility statement.
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.
Insulation rebates in North Castle
With 58.6% of the town on fuel oil, most North Castle
households have no gas-utility rebate pathway at all, and the electric side is
not currently offering one either. Con Edison serves the town
for both gas and electricity, and its residential Weather Ready
weatherization program is not accepting applications. Con
Edison’s own page tells Westchester customers to expect news about 2027
incentives and to use NYSERDA in the meantime. A $4,000 Con Edison
weatherization figure still sitting on one of Con Edison’s own index pages is
stale.
The live program is NYSERDA Comfort Home:
$2,500 to air seal and insulate the attic and rim joist,
$3,000 if wall and floor insulation is added, and
$2,000 more toward ENERGY STAR windows afterwards. The
contractor has to be on NYSERDA’s Comfort Home list and the house has to meet
the conditions of the whole package. Households at or below 80% of area median
income should look at EmPower+: no cost up to
$14,000 downstate, or half the cost up to
$7,000 at moderate incomes. See
the full New York rebate guide for the
mechanics.
The federal Section 25C tax credit ended for anything placed in service after
31 December 2025. There is no federal insulation credit on a
2026 job.
Code and climate in North Castle
The 1960s is the biggest decade in this town, which means the largest block
of North Castle houses was built before energy performance was something an
inspector measured. The current rulebook is the 2025 Energy Conservation
Construction Code of New York State, in force since 31 December
2025 and based on the 2024 IECC. Westchester is climate zone 4.
For new construction and additions it sets R-49 in the
ceiling, R-30 in wood-framed walls (or R-20 plus R-5
continuous), R-30 in floors, and R-15 continuous or R-19 cavity in basement and
crawl space walls. Anyone quoting R-60 is quoting Connecticut’s code.
None of it applies to a house already standing. The code
expressly does not require an existing building to be altered, only that an
alteration not leave you with less than you had. ENERGY STAR recommends R-60 for a retrofit attic here, which is guidance, not
law.
Common questions about insulation in North Castle
Do you install insulation in North Castle, NY?
Yes, across the whole town, including Banksville and North White Plains. Most
of what we do here is 1960s and 1970s detached houses on fuel oil. If your house
is in Armonk and was built in the 1990s or later, the
Armonk page covers a different
set of problems.
How much does insulation cost in North Castle?
Most projects run $3,500 to $12,500. A 1960s ranch attic with a chimney chase
to seal and a rim joist to close sits near the bottom. A bigger house with
several roof planes, a room over the garage and settled fill to clear sits
higher, because the day goes into access and air sealing before any material is
installed.
Are there insulation rebates in North Castle?
Yes, through NYSERDA rather than the utility. North Castle is Con Edison, and
Con Edison’s Weather Ready program is not accepting applications, so Comfort
Home is the live one: $2,500 for air sealing plus attic and rim joist, $3,000
with walls and floors added. EmPower+ covers income-qualified households. No
federal credit applies to a 2026 job.
My 1960s North Castle house has R-11 walls. Should I do the walls too?
Usually not first. The attic plane, the rim joist and the air sealing return
more per dollar than dense-packing walls, and on many houses that is where the
job should stop. Walls are worth doing when the siding is coming off anyway,
when rooms on the windward side stay cold after the attic is finished, or when
you want the $3,000 Comfort Home tier, which requires them.
Free energy audit in North Castle
We walk the attic, the basement and the rim joist, look at the eaves and the
chimney chase, and give you a written scope and a price. No charge, no
obligation. If your attic depth is acceptable and the money belongs in the rim
joist and a bath fan venting into the soffit, that is what the report will
say.
Call 914-825-6824 or use the form on this page. Open
8am–8pm, seven days. We have insulated hundreds of homes across New York,
Connecticut and New Jersey with a 100-plus in-house crew.