R 25 Rigid Roof Insulation Thickness
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.
R 25 rigid roof insulation thickness. Please consider this extra thickness requirement when designing blocking heights and specifying fastener lengths. Foamular thermapink 25 owens corning insulation. Benefits of energyguard polyiso roof insulation include. Excellent lttr value compared to any other fm class 1 rated products of equivalent thickness.
In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7. Eight inches of poor quality insulation may have a higher and better r value than one inch of top quality insulation. As a foil faced polyisocyanurate foam insulation enerfoil tm s r value actually more than doubles. Because rigid foam plastic insulation products are not all aged in accordance with the same standards it is useful to publish comparison r value data.
For every type and material of insulation check the r value per inch of thickness that the manufacturer has listed. So you need to know an insulation product s thickness as well as its r value in order to compare it to another product. R value is a measurement of thermal resistance and measures the ability of heat to transfer from one side of an object to another. R values vary depending on many factors including the mean temperature at which the test is conducted and the age of the sample at the time of testing.
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. 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. Owens corning insulation products help improve thermal performance and control moisture in commercial institutional and. A higher insulation r value usually means a higher price point as well.
All products in the acfoam polyiso roof insulation family are closed cell rigid foam insulation board flat or tapered. Firestone iso 95 gl polyiso insulation has a higher r value than other insulation products while also outperforming competitive polyiso at low temperature. Foamular xps roof insulation for commercial buildings page 5 foamular xps roof insulation for commercial buildings foamular xps insulation is a rigid foam insulation which meets the needs of today s design professionals for a truly sustainable insulation product. As a benchmark one inch of solid wood has an r value of 1.
When it comes to insulation performance the difference is in the details.