Polyiso Roof Insulation R Value

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 roof insulation r value.

The r value test method and the long term thermal resistance lttr methodol ogy. All products in the acfoam polyiso roof insulation family are closed cell rigid foam insulation board flat or tapered. And nrca s r value recommendations associated with the use of polyisocyanurate insulation used in roof systems. More projects select polyiso roof insulation for both new and roof replacement systems than any other insulation product.

Tapered polyiso minimizes the negative effects of ponding water and extends the service life of a roof. 1 2014 industry issue update polyiso s r value provided an overview of the theory of foam aging. Excellent lttr value compared to any other fm class 1 rated products of equivalent thickness. Understanding r value thursday december 13 2018 what does r value mean.

Benefits of energyguard polyiso roof insulation include. A higher r value means that the insulation will do a better job of holding in conditioned air whether that s heat in the winter or cool air in the summer. For a very good introductory overview article on r value see r values over at the website of. You should of course see the manufacturer provided technical data sheet for the r value of specific products.

Ashrae climate zone iecc 2012 r value requirements polyiso thickness to meet iecc old lttr method new lttr method 1 2 3 r 20 2 layers 1 7 2 layers 1 8 4 5 r 25 2 layers 2 1 2 layers 2 2 6 r 30 2 layers 2 5 2 layers 2 6. Polyiso has a high r value per inch compared to other insulation products. When it comes to insulation performance the difference is in the details. 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.

With premium polyiso manufacturing atlas is able to produce the highest effective r values with minimal material thickness. Please consider this extra thickness requirement when designing blocking heights and specifying fastener lengths. 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. Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials.

Carlisle s tapered insulation helps promote rooftop drainage while providing excellent insulating value. All atlas acfoam polyiso insulation boards are qualitymark certified providing consumers an easy way to identify premium products that meet or exceed building codes for the best in roof performance.