There are two general categories of SPF insulation materials; open-cell, low-density and closed-cell, medium-density. Both foam categories provide excellent insulation and air sealing. Although both are made using almost identical chemical reactions, there are some inherent physical property differences that often determine which product is chosen for a particular project.

• Open-Cell Spray Foam: Also known as a low-density spray foam and consistently outperforming traditional insulation types, this spongy foam provides excellent thermal insulation and air sealing. Open-cell foam products can also provide sound attenuation and allows leaks to drain through them letting you identify leaks sooner for repair. Ideal for filling walls, ceilings and crawlspaces, open cell foam spray is impermeable to air thereby helping to reduce escaping air but is permeable to moisture to help control moisture movement.
• Closed-Cell Spray Foam: This rigid spray foam with a higher R-value (resistance to heat flow) per inch, is a medium density that performs brilliantly in flood-prone areas since it can reject bulk water. In fact, FEMA recognizes closed cell foam as a flood-resistant material. Closed-cell foam can be used effectively in both interior and exterior applications and is ideal for continuous insulation applications in commercial buildings.