Spray Foam vs. Batt Insulation: What’s the Difference?

Batt insulation — the familiar rolled or pre-cut panels — is one of the most widely used insulation materials, fitted between wall studs, floor joists, or attic rafters. It's straightforward to install in regularly shaped spaces and has been a standard choice for decades.

Spray foam works differently: it's applied as a liquid that expands to fill the space it's sprayed into, including gaps, cracks, and irregular corners that batt insulation can't easily reach. As it expands and cures, it also creates an air barrier, sealing out drafts along with insulating.

Neither option is universally "better" — it depends on the space. Batt insulation is often a practical fit for regularly framed walls and floors, while spray foam tends to shine in irregular areas, rim joists, or anywhere sealing air leaks matters as much as insulating.

A professional assessment can help determine which approach — or combination of both — makes the most sense for your specific home.