Johns Manville (JM) has announced that JM Corbond III® closed-cell spray polyurethane foam insulation now delivers an R-value of R-7 per inch, a change that translates to a 9-percent increase in thermal resistance compared to the previous R-6.4 per inch.
International Codes can be confusing. The 2012 International Energy Conservation Code (IECC) includes new standards for almost every component in the building envelope, and these standards are further increased in the new International Green Construction Code (IgCC), which serves as an overlay code.