Technology Today

An end to a debate?

Since the early 1980s, there has been an ongoing debate in the U.S. roofing industry regarding the long-term thermal performances of rigid board polyisocyanurate insulation used in low-slope roof assemblies.

If you are involved in the design or installation of low-slope roof assemblies using polyisocyanurate insulation, you should be familiar with recent and upcoming developments regarding this issue.


In November 1987, NRCA and the Midwest Roofing Contractors Association issued a joint technical bulletin regarding the in-service R-value for polyisocyanurate and polyurethane roof insulation boards.

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