Closed-cell polyurethane spray foam is known to be the most common of the two. Its considered a closed cell due to its high R-value. The R-value is the materials capacity to insulate and resist ...

Closed-cell polyurethane spray foam has some pretty awesome qualities. It has a high R-value. Its resistant to water, mold and insects. It expands into hard-to-reach nooks and crannies.