The Polyisocyanurate Insulation Manufacturers Association (PIMA) recently issued "Measuring the R-value of Polyiso Roof Insulation," attempting to refute NRCA's design R-value recommendation. To read PIMA's performance bulletin, click here.

In January, NRCA issued an Industry Issue Update explaining the rationale for a revision of its design in-service R-value recommendation in its 2015 manual. To view the Industry Issue Update, click here.

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