Frequently Asked Questions

National guides put installed spray foam at $1.50 to $5.00 per square foot (HomeGuide), with whole-house jobs from about $8,000 to $30,000 depending on the source. Older Yonkers houses with tight access often run higher per foot. We price your house after seeing it, and the written estimate is the price.

Closed-cell is usually better for rim joists, foundation walls, garage ceilings and shallow roof slopes because it is dense, rigid and slows moisture. Open-cell is usually better for filling roof lines and open walls where stopping air is the main job. Many houses get both.

The New York State energy code places Westchester County in Climate Zone 4, and the code lists R-49 for ceilings. That applies to new work and renovations, but it is also a sound target when you add insulation to an existing attic.

No. Yonkers and the rest of Westchester follow the Energy Conservation Construction Code of New York State, enforced by each city, town or village building department. The NYC code covers only the five boroughs.

Con Edison's Weather Ready program is closed to new applications. NYSERDA's Comfort Home program lists $2,500 and $3,000 packages and an extra $1,000 for Westchester homeowners who are not eligible for Weather Ready. Incentives require a participating contractor, so confirm eligibility first.

Usually, yes. Closed walls are filled through small holes with dense-pack cellulose or an injection foam, then the holes are patched. Open-cell spray foam is for walls that are already open during a renovation.

Regular insulation such as fiberglass or cellulose slows heat but lets air pass through and around it. Spray foam bonds to the framing and stops air movement as well as slowing heat. That is why foam is used where air leaks are concentrated, like rim joists and roof lines.

It depends on the product. HomeGuide advises vacating for at least 24 hours with many foams. We give you the exact time for the product on your job and ventilate the work area.

Not usually. Foam needs to bond to clean framing or sheathing, so old batts are pulled out of the areas being foamed. Removal is listed as its own line on the quote.

No, and it can hide one. Roof leaks are fixed by a roofer first. We check for stains and damp sheathing before spraying any roof line.

The state energy code places Westchester in Climate Zone 4 and lists R-49 for ceilings. It applies to new construction and renovation work; for an existing attic it is a good target rather than a legal requirement.

Usually because the attic floor is leaky and thinly insulated, so roof heat comes straight down. Kneewalls with no air barrier behind them make it worse. Sealing and insulating those surfaces is the fix.

Not always. Dry, clean insulation can stay and be topped up after sealing. Wet, moldy, rodent-damaged or very compressed material should come out, and we price that separately.

Warm air leaking into the attic heats the roof, snow melts and refreezes at the cold eaves. Sealing the attic floor and adding insulation keeps the roof colder and is the lasting fix.

In most older houses, yes. It is a small area but it leaks air along the entire perimeter, and sealing it often makes first-floor rooms noticeably warmer. NYSERDA's Comfort Home base package pairs the rim joist with the attic for that reason.

It is common but not ideal. Batts do not stop air, and warm basement air can condense on the cold rim behind them. Closed-cell foam or sealed foam board avoids that.

Fix the water first. Grading, gutters, cracks and drainage come before insulation. Once the wall stays dry, closed-cell foam is the safest choice against stone or concrete.

Foam in a living space generally needs a thermal barrier such as drywall. In some unfinished areas, other coverings or rated products may be acceptable. We note what your space needs on the quote.

Yes. Dense-pack cellulose or injection foam goes in through small holes in each stud bay, from outside or inside, and the holes are patched. The plaster stays in place.

Standard spray foam needs open cavities. Closed walls use dense-pack cellulose or a low-expansion injection foam instead.

Live knob-and-tube wiring should be evaluated by an electrician before walls are filled. We check for it during the survey.

Wall insulation alone rarely makes an old house tight. If we also do heavy air sealing, we talk about ventilation and combustion appliance safety as part of the plan.

The floor has unheated garage space beneath it, and the insulation in the joists often does not touch the subfloor or is open at the ends. Cold air moves through the bays. Sealing the ends and filling the bays fixes it.

Not always. Bays can often be dense-packed through small holes. If the ceiling is coming down anyway, closed-cell foam against the subfloor is the stronger option.

Foam on the underside of the roof deck brings the space behind the kneewalls inside the insulated envelope, so it can be used for storage or opened up in a renovation.

Yes, though small foam jobs often meet a minimum. Pairing the room with attic or rim joist work on the same visit makes better use of it.

Only if it is wet, moldy, contaminated or in the way of air sealing. Clean, dry insulation can often stay and be topped up after sealing.

Loose fill is vacuumed through a hose to a bag outside, so it does not travel through the house. Batts are bagged by hand and carried out along a protected path.

Leave it alone and have it tested. If it contains asbestos, a licensed abatement contractor must remove it. We can insulate after it is gone.

HomeAdvisor lists removal at $1 to $2 per square foot, with typical jobs around $600 to $1,200. Contamination, access and disposal change the figure, and our written estimate is the price.