Insulation is the quiet workhorse of an efficient home. It slows the heat that escapes in winter and the heat that pushes in during summer, and choosing the right material for each part of your house is what separates a drafty, expensive home from a steady, comfortable one. Here is a clear look at the main types we install across Westchester, Rockland, and Bergen County — how each one works, where it belongs, and what to expect.
A quick note on R-value: it measures a material's resistance to heat flow, so a higher number per inch means more insulating power in less space. It is the single most useful figure when comparing your options.
Spray Foam Insulation
Spray foam is applied as a liquid that expands in seconds to fill cavities, gaps, and irregular spaces other materials leave open. It comes in two forms, and the difference matters.
Closed-Cell Spray Foam
Closed-cell foam is dense and rigid once cured. It delivers roughly R-6 to R-7 per inch — the products we install are rated at R-6.9 to R-7.1 per inch — the highest R-value per inch of the products we install. Because its cells are sealed, it acts as both an air barrier and a vapor barrier, blocking moisture and adding structural stiffness to walls and roof decks. It is the strongest choice for rim joists, basement and crawlspace walls, cathedral ceilings, and any spot where space is tight or moisture is a concern.
Open-Cell Spray Foam
Open-cell foam is softer and lighter, at about R-3.9 to R-4.2 per inch. It is more breathable, expands more to fully fill framing cavities, and costs less. It makes an excellent air sealer for interior walls and attics, where its ability to breathe helps manage moisture and its sound-dampening quality is a welcome bonus.
What to expect during install: the area is masked off, our crew sprays in even passes, and the foam sets within minutes. The workspace needs to be vacated for a few hours while it cures and ventilates — we handle the containment and cleanup.
Fiberglass Batt and Blown-In Insulation
These are the traditional, cost-effective materials, and they are still the right answer in many homes.
- Fiberglass batt: pre-cut rolls that deliver about R-3 to R-4 per inch. Batts fit neatly between standard studs and joists, making them a practical, budget-friendly choice for open walls, floors, and attic bays. Proper fit is everything — gaps and compression sharply reduce performance.
- Blown-in insulation: loose fiberglass or cellulose blown in to form a seamless blanket. It shines in attics and hard-to-reach cavities because it flows around wiring, framing, and odd angles with no seams. Cellulose runs roughly R-3.2 to R-3.8 per inch; blown fiberglass a bit less per inch.
For attics in our climate, the U.S. Department of Energy recommends building up to roughly R-49 or higher. Many older suburban homes were built with a fraction of that, which is why an attic top-off is one of the fastest-paying upgrades we do.
Rigid Board, Air Sealing, and Weatherization
Rigid foam board is a stiff panel used on foundation walls, under slabs, and on the exterior of a home to break thermal bridges — the framing paths that let heat sneak around cavity insulation. Depending on the foam type, board delivers about R-4 to R-6.5 per inch.
Just as important as any material is air sealing. A home can be packed with insulation and still feel drafty if air leaks freely through gaps around wiring, plumbing, top plates, and attic hatches. We seal those leaks with foam, caulk, and weatherstripping so the insulation you paid for can actually do its job. Insulation slows heat; air sealing stops the drafts — you need both, and together they typically trim monthly bills by 20% or more.
Every home is different, and the best system usually blends two or three of these materials matched to your walls, attic, and budget. The Home Insulators has been a family-owned company serving NY and NJ homeowners since 2015, and we start every project with a free energy audit that shows you exactly where your home is losing energy and what it will take to fix it. Call us today at 914-825-6824 to schedule yours.