At the final code hearings May 21, 2007 in Rochester, NY the International Code Council (ICC) approved the use of closed cell SPF as insulation over ducts in attics and crawl spaces for residential buildings. The code change was approved in the International Energy Conservation Code (IECC) and the International Residential Code (IRC) however, it was not approved in the International Mechanical Code (IMC). Because the IMC takes precedence in the International Building Code, SPF is not yet approved as insulation on ducts inside attics and crawl spaces of commercial buildings.

Supporters speaking in behalf of the code changes at the final hearing included, Bob Braun (proponent of the code change), JoAnn Surma, Dow Chemical, Jesse Beitel, Hughes and Associates, Laverne Dalgleish, Air Barriers Association of America and Mason Knowles, Mason Knowles Consulting.

Key elements to the approval of the code change included providing minimum perm ratings of the SPF and a specific reference to compliance of the plastics section of the code regarding thermal and ignition barriers.

Mason Knowles reports " A Massive amount of energy is lost each year to poorly sealed and insulated ducts in attics and crawl spaces. This code change makes a lot of sense. SPF installed to existing ducts will seal and insulate making the ducts much more efficient in both warm and cold climates."

Results of the code changes can be downloaded at the ICC website ICC code changes are adopted on an 18 month cycle but the main ICC code books are published every 3 years. The latest ICC code books were printed in 2006. So this code change will be published in the ICC supplementary code change book later this summer.