Polyisocyanurate Roof Insulation R Values

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.

Polyisocyanurate roof insulation r values.

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. Dated its r value recommendations for polyisocyanurate insulation used in roof systems. 1 when joints penetrations detailed appropriately. In the nrca roofing manual.

As an example a 1 board label will include information from lttr s770 03. The information on this page is based on data considered to be true and accurate based on periodic internal. Polyiso insulation is the best choice as a cost effective energy efficient and environmentally responsible insulation product. Polyisocyanurate polyiso is a closed cell rigid foam insulation board made with recycled content that is widely used in commercial roofing.

Recommended reading for anyone specifying polyiso insulation. Benefits of energyguard polyiso roof insulation include. 2 stated thermal resistance values are based upon conditioning requirements and test methodology found in astm c1289 and astm c518 for foil faced polyisocyanurate 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.

This industry issue update explains why the nrca recommends using a significantly lower r value for polyiso than pima does. Firestone iso 95 gl polyiso insulation has a higher r value than other insulation products while also outperforming competitive polyiso at low temperature. More projects select polyiso roof insulation for both new and roof replacement systems than any other insulation product. Polyiso has a high r value per inch compared to other insulation products.

See also material data sheet msds 1511 or msds 1911. Excellent lttr value compared to any other fm class 1 rated products of equivalent thickness. Jm sheathing r values will not change. Membrane roof systems 2011 and the nrca roofing manual.

Tapered polyiso minimizes the negative effects of ponding water and extends the service life of a roof. What is polyiso insulation. Jm s wall sheathing line ap foil and ci max are not governed by lttr test methods and have different r value measurement standards. Firestone isogard polyiso insulation goes even further and was the first product on the market to meet both astm c1289 required and recommended thermal performance values.

Membrane roof systems 2015 nrca had recommended designers use in service r values of 5 0 per inch thickness in predominant.