Polyisocyanurate Roof Insulation R Value Per Inch

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

Polyisocyanurate roof insulation r value per inch.

This allows polyiso products to deliver more energy savings potential for buildings than other materials of the same thickness. Polyiso has a high r value per inch compared to other insulation products. Excellent lttr value compared to any other fm class 1 rated products of equivalent thickness. Rmax thermasheath 3 2 in.

Let s use the r value of iko s polyiso insulation enerfoil tm as an example. Lttr value published by polyisocyanurate insulation manufacturers for 1 and 1 5 inch thick samples. Jm revised lttr values. Polyiso has a high r value per inch when compared to other insulation products see chart below.

Not all industry stakeholders are in agreement with the r 6 in. Firestone iso 95 gl insulation the highest thermal ratings. 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. 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.

In the nrca roofing manual. Since 1987 the national roofing contractor s association nrca has recommended designers use r 5 6 in. As a reasonable estimate of the actual thermal performance of polyisocyanurate insulation over the lifespan of a roof assembly. R 13 1 polyisocyanurate rigid foam insulation board.

R value per inch comparison polyiso offers a r 6 5 and the highest r value per inch when compared to other insulation. R 6 polyisocyanurate rigid foam insulation board. Because it s highly energy efficient with the highest r value ratings per inch the use of iso 95 gl insulation in a firestone roofing system provides a cost effective solution for today s oof design r challenges and is preferred for any and every roofing system. Membrane roof systems 2015 nrca had recommended designers use in service r values of 5 0 per inch thickness in predominant.

Polyiso still remains the highest r value per inch of any available insulation. Jm suggests that design professionals use 5 7 r inch as a design specification for its foam products. Benefits of energyguard polyiso roof insulation include. Membrane roof systems 2011 and the nrca roofing manual.