Green building standards recommend use of a variety of new thermal insulation products. However, durability of wooden framing used in conjunction with new insulation materials has not been thoroughly examined, specifically in reference to interstitial condensation. This research used a single-sided hot-box design to measure moisture content of wood framing during a 60-day period. The resulting moisture content of the wood framing was compared as tested with spray-applied cellulose and polyurethane versus fiberglass batt insulation. The average moisture content of framing insulated with cellulose and polyurethane was greater than framing insulated with fiberglass. Based on the results from this research, the use of spray-applied cellulose and polyurethane insulation materials may increase the risk of structural durability.

Green building standards, such as LEED for Homes or the National Green Building Standard, emphasize creating energy efficient structures to limit negative impact on the environment. Green building practices employed to increase energy efficiency of the building enclosure may overlook possible adverse effects that these practices may have on structural durability. Because spray-applied cellulose and polyurethane insulation increase moisture content of wooden framework within building enclosures, it can be deduced that energy efficient insulation may increase risk of moisture-related biodeterioration of the building enclosure. After review of points awarded for insulation materials within LEED for Homes and the National Green Building Standard, results from this study imply that the National Green Building Standard does not emphasize durability of wooden structures in their guidelines at the present time.