Insulation FAQ for Long Island Homeowners
The questions we get every week from Long Island homeowners. Materials, cost, timelines, permits, warranties, insurance. If yours is not here, call us.
How much does it cost?
For a typical 2,000 sqft home, expect $1,800 to $4,800 for fiberglass batts, $2,200 to $5,500 for blown-in cellulose, $2,800 to $7,500 for open-cell spray foam, $3,500 to $9,500 for closed-cell spray foam, and $8,500 to $22,000 for a full whole-home envelope retrofit. NYSERDA Comfort Home rebates cut $1,500 to $5,000 off those numbers; EmPower+ can cover up to 100% for income-qualified households. Try our free estimator for a ballpark on your house.
No. The walk-through is free. The written quote is free. There is no obligation, no deposit to hold a date, and no follow-up pressure. If you want to think about it for six months, go ahead.
House size, number of stories, the condition of what is underneath, how many windows and doors (each one needs trim and flashing), material tier, and whether you need asbestos abatement. Two houses on the same street can be $10,000 apart. That is why we do a walk-through before quoting.
Yes. We work with multiple lending partners and offer 0% promotional financing for qualified homeowners. Soft-pull pre-qualification takes about two minutes. See our financing page for details.
Yes — indirectly but measurably. Energy Star-rated homes sell 2-8% higher than comparable homes per the DOE, and a documented blower-door and insulation upgrade shows up on a pre-listing energy audit. In competitive Nassau and Suffolk housing markets, a proven low-utility-bill history is a real buyer signal, especially for oil-heated homes.
We are mid-range for quality contractors. You can find cheaper, but those crews are usually unlicensed, uninsured, or using subcontractors they have never worked with. You can find more expensive, but the premium is usually overhead, not craftsmanship. We price to cover a full-time crew, factory-certified installation, and a real 10-year workmanship warranty.
How does it work?
Most residential insulation jobs take 1 to 5 working days. A single-scope attic air-seal + blown-in cellulose is usually one day. A basement rim-joist and wall spray-foam project is 1 to 2 days. Full whole-home envelope retrofits — attic, walls, basement, and crawl space — run 3 to 5 days. Weather rarely affects interior insulation work.
Yes. We handle all permits for both Nassau and Suffolk County. The cost is included in your quote. We know every building department on the island, which ones need engineer stamps, and which inspectors want to see specific things.
We almost always tear off. Going over existing insulation hides problems, adds weight, and voids some warranties. If your existing insulation is sound and code allows it, we can discuss an overlay, but we will tell you honestly whether it makes sense.
We photograph it, send it to you immediately, and get your approval before any extra work. Rotted sheathing repair typically runs $600 to $2,400 depending on extent. There are no surprise charges on our invoices.
Yes, for the duration of the job. We place plywood under it to protect the driveway. It gets picked up the day after we finish. We clean the jobsite at the end of every work day, not just at the end of the project.
Yes — insulation work is mostly interior, so weather barely matters. Closed-cell spray foam requires a substrate above 40°F, which we manage with portable heaters if needed. Attic blown-in cellulose and wall dense-pack can be installed any day of the year. Winter is actually our busiest season because homeowners feel the cold the most when the oil truck pulls up.
No. Most homeowners leave a key or a garage code and go to work. We will text you a photo update at the end of each day. If we find anything unexpected behind the old insulation, we call you immediately for approval before doing any additional work.
Which insulation is right?
There is no single best — the assembly dictates the material. Open attic floors: blown-in cellulose or fiberglass over an air-sealed ceiling plane, R-49 minimum, R-60 preferred. Attic rafters / cathedral ceilings: open-cell spray foam. Empty existing wall cavities: dense-pack cellulose from the exterior. Basement rim joists and foundation walls: closed-cell spray foam. Crawl spaces: full encapsulation with a 20-mil vapor barrier and closed-cell foam on the walls. We walk through the pros and cons for your specific house during the BPI energy audit.
For most Long Island homeowners who plan to stay 10+ years, yes. At R-7 per inch it is the highest-performing product available, it doubles as a vapor barrier, and it adds structural rigidity to walls. It is the right call for basements, rim joists, crawl spaces, and cathedral ceilings where moisture or space is tight. For big open attics where you have room to pile up material, blown-in cellulose at R-3.7 per inch usually gets you the same R-value for half the cost.
Yes — and it is the single biggest lever. BPI data shows 20 to 40% of a typical LI home's heat loss is air leakage, not conduction through insulation. Sealing top plates, rim joists, can lights, and attic hatches before blowing insulation over them multiplies the value of every R-unit you add. A blower door test before and after proves the number.
Long Island is climate zone 4, so the 2020 Energy Code calls for R-49 in the attic and R-20 in above-grade walls. We usually recommend R-60 in attics if you have the depth — the marginal cost is small and the payback is fast. For NYSERDA Home Performance rebate eligibility, the audit will tell you exactly what upgrade is going to trigger the biggest incentive for your specific house.
Yes, and it is often the right call. A common Long Island combination is closed-cell spray foam on the basement rim joist and crawl space walls, plus blown-in cellulose in the attic. We can also do a hybrid wall assembly with 2 inches of closed-cell against the sheathing plus dense-pack cellulose fill for a full air barrier at a lower price than all-foam. We will show you the math during the BPI-certified energy audit so you can see which mix is best for your house.
What is covered?
10-year workmanship warranty on every job, in writing. That covers our labor and installation. Material warranties come from the manufacturer and range from 25 years (fiberglass) to lifetime-of-structure (closed-cell spray foam). Because we are Demilec-certified, the manufacturer warranties are fully honored.
Most standard homeowners policies cover sudden storm damage to insulation. We work with insurance adjusters regularly and can help you through the claims process. We document the damage, provide the scope of work, and meet the adjuster on site if needed.
Very common on pre-1978 Long Island homes, especially in Levittown, Hicksville, and Farmingdale. If asbestos is present, we coordinate licensed abatement. Typical cost is $3,500 to $6,500 depending on house size. We handle the testing, abatement coordination, and disposal paperwork.
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