Canada and U.S. standards become consistent
The National Building Code of Canada adopted the most recent version of CAN/ULC-S704-11, the Canadian polyisocyanurate standard specification, which references the CAN/ULC-S770-09 test method to determine the long-term thermal resistance (LTTR) of polyisocyanurate foam insulation. The adoption will help bring consistency to the test methods used for measuring LTTR between Canada and the U.S. The U.S. uses ASTM C1289, "Standard Specification for Faced Rigid Cellular Polyisocyanurate Thermal Insulation Board," to predict the LTTR R-values for a variety of polyisocyanurate insulation boards.
"Because our members make and ship products in the United States and Canada, it is critical polyiso insulation be subjected to the same criteria for measuring LTTR in both countries," says Jared Blum, PIMA's president. "Together, these standards provide more data for predicting the long-term thermal performance of polyiso insulation and further enhances the validity of PIMA's QualityMarkCM program."
PIMA's QualityMark program is the only third-party program for certification of polyisocyanurate insulation's thermal value. To participate in the QualityMark program, a Class 1 roof needs to have a design R-value of 5.7 per inch.