Older homes in Staten Island and the New York City area have a lot going for them — solid construction, established neighborhoods, and character that newer builds rarely replicate. What many of them don’t have is adequate insulation. The standards that governed how homes were built in the 1950s, 60s, and 70s look very different from what’s available today, and the gap shows up every winter in heating bills and every summer in rooms that never quite cool down the way they should.
Siding replacement tends to be the moment homeowners finally address that gap. When the exterior cladding comes off, the wall cavity is exposed in a way it almost never is otherwise. That’s a window of opportunity that closes the moment new siding goes on, which is why if you ever wanted to replace your siding or, alternatively, if you ever wanted to improve your insulation, combining both is the best option.
What Older Homes Are Working With
Homes built before the 1980s were constructed without much consideration for thermal performance. Many have little to no insulation in the wall cavities. Those that do often have materials that have settled, degraded, or never performed particularly well to begin with. Vermiculite, old fiberglass batts that have compressed over decades, or simply nothing at all — these are common findings when siding comes off a home that’s been standing since the Eisenhower administration.
The building envelope in these homes — the combination of walls, roof, windows, and foundation that separates conditioned interior space from the outside — was simply not designed with energy efficiency as a priority. The result is a house that works harder than it needs to in order to stay comfortable, and a homeowner who pays for that inefficiency in their utility bills year-round.
The Wall Cavity Problem
When exterior siding is replaced without addressing what’s behind it, the thermal performance of the wall stays exactly what it was. New siding improves curb appeal, weatherproofing, and durability — all valuable — but it doesn’t compensate for an empty or degraded wall cavity on its own.
Insulating the wall cavity during a siding replacement project typically involves one of two approaches. The first is blown-in insulation — cellulose or fiberglass — injected into the wall cavity through small holes drilled in the sheathing before new siding goes on. This approach works well for walls where access from the exterior is cleaner than trying to open up interior walls. The second is rigid foam board insulation installed over the sheathing before the new siding goes on, which adds a continuous thermal barrier across the entire wall surface rather than just filling the cavity.
Both approaches have merit, and the right one depends on the existing wall construction, the condition of what’s already in there, and the overall scope of the project. The important thing is that the conversation happens before siding goes on — not after.
Continuous Insulation and Why It Matters
One of the most significant advances in residential insulation over the past few decades is the concept of continuous insulation — a layer of rigid foam board that runs uninterrupted across the exterior of the wall, covering studs and framing members as well as the cavities between them.
Traditional cavity insulation has a limitation that’s easy to overlook: wood studs conduct heat. In a wall that’s only insulated between the studs, the framing itself creates pathways for heat to move through the wall. These are called thermal bridges, and they meaningfully reduce the effective performance of the insulation in the cavities. Continuous rigid foam insulation over the exterior sheathing eliminates that problem by wrapping the entire wall in a consistent thermal layer.
For older Staten Island homes — particularly wood-framed colonials, capes, and ranches built in the postwar decades — adding continuous insulation under new siding can produce a noticeable improvement in comfort and a measurable reduction in heating and cooling costs. It also adds to the overall durability of the wall assembly by keeping moisture away from the sheathing.
What to Watch for in Older Homes Specifically
Homes of a certain age sometimes present complications that newer construction doesn’t. A few things are worth knowing before a siding and insulation project gets underway on an older property.
Lead paint is a consideration in homes built before 1978. Exterior paint on older siding may contain lead, and its removal or disturbance during a project needs to be handled appropriately. A contractor working on pre-1978 homes should be aware of the relevant EPA requirements around lead-safe work practices.
Asbestos siding was used on many homes built from the 1920s through the 1970s, often in the form of asbestos cement shingles. If the home has original siding from that era that hasn’t been replaced, it needs to be tested and handled by professionals qualified to work with asbestos-containing materials before any demolition or removal begins.
The condition of the sheathing underneath old siding can also be variable. Older board sheathing — diagonal planks rather than plywood or OSB panels — is common in homes of this age, and its condition affects what insulation and installation methods are appropriate. A thorough inspection before the project scope is finalized helps avoid surprises once the siding comes off.
Making the Most of the Project
A siding replacement is a significant investment regardless of the material chosen. Fiber cement, vinyl, and engineered wood all offer different performance characteristics, price points, and aesthetics — but none of them do too much for the thermal performance of the wall on their own, even if you choose energy efficient siding. Pairing the siding project with insulation work is the most cost-effective way to address both issues at once, because the labor involved in exposing the wall is already part of the project.
The same logic applies when windows or doors are being replaced at the same time — each one is an opportunity to air-seal and insulate the rough opening properly, which is often done poorly or not at all in older construction. Addressing the whole exterior envelope together, rather than one component at a time, tends to produce better results and makes the most of the disruption involved in a major exterior project.
Christian Construction has been working on Staten Island homes since 1999 and is a CertainTeed 5 Star Contractor with experience on properties of all ages, including older homes with the specific challenges they tend to present. If you’re planning a siding replacement and want to talk through the insulation side of the project at the same time, call 718-447-6475 or reach out through the contact page for a free estimate.
