Full expansion foam to fill holes and voids seals and insulates. Bonds to most surfaces, tack free in 30 minutes, can be sanded or painted with in hour. Home Seal is an all-purpose minimum expanding foam sealant designed to fill smaller cracks and voids in both indoor and outdoor applications. It can be used to fill small gaps in walls, around exhaust vents, plumbing fixtures, baseboards, sill plates, siding edges, skylights and more.