Polyiso Roof Insulation R Values

Dated its r value recommendations for polyisocyanurate insulation used in roof systems.

Polyiso roof insulation r values.

More projects select polyiso roof insulation for both new and roof replacement systems than any other insulation product. Polyiso roof insulation is the most widely used product for low slope commercial roofing and provides a high r value that helps meet today s energy code requirements without the added thickness or weight of other products. At one inch thickness enerfoil tm achieves a 6 2 r value or a 1 08 rsi. But what does that mean and how do researchers determine r value.

Tapered polyiso minimizes the negative effects of ponding water and extends the service life of a roof. In the nrca roofing manual. Polyiso is unique in that the r value increases with the thickness of the foam so three inches of polyiso has a higher r value per inch than two inches. Polyiso has a high r value per inch compared to other insulation products.

Resista 1 polyisocyanruate insulation board has a ul class a rating for fire resistance when used over combustible decks and is compatible with single ply and modified bitumen roofing systems. Polyiso still remains the highest r value per inch of any available insulation. Fm approved subject to the conditions of approval as a roof insulation when installed as shown in the current edition of the factory mutual research approvals guide. Closed cell polyisocyanurate polyiso foam core integrally bonded to non asphaltic fiber reinforced organic felt facers.

To compare different insulation products researchers have to create the exact same conditions and then measure how well the insulation performs. Jm revised lttr values jm suggests that design professionals use 5 7 r inchas a design specification for its foam products. Membrane roof systems 2011 and the nrca roofing manual. Jm is proud to be a pima member and have its product third party certified under the pima quality mark program.

Benefits of energyguard polyiso roof insulation include. Membrane roof systems 2015 nrca had recommended designers use in service r values of 5 0 per inch thickness in predominant. Measuring the r value of polyiso roof insulation at the website of pima polyisocyanurate insulation manufacturers association discusses long term thermal resistance lttr the astm standards underlying the r values for polyisocyanurate insulation and provides r values for various thicknesses of polyiso which increases in r value per inch as total thickness of the installation increases. Excellent lttr value compared to any other fm class 1 rated products of equivalent thickness.