Polyisocyanurate, also referred to as PIR, polyiso, or ISO, is a thermoset plastic typically produced as a foam and used as rigid thermal insulation. Polyiso Insulation board is made of glass fiber-reinforced cellulosic felt facers bonded to a core of isocyanurate foam.
Polyiso is unique in that the polyiso insulation R-value increases with the thickness of the foam, so three inches of polyiso has a higher R-value per inch than two inches.
Light weight –– Lighter than most other roofing insulating products offering comparable thermal resistance; as much as five times lighter in weight than many other materials with the same R-value.
Low water permeability –– lower overall perm rating than many conventional insulation boards.
Uses for PolyIso Insulation Board
Polyiso Roof Insulation is designed for use over structural roof decks where R-values of 5.7 or higher are required, along with comprehensive UL and FMRC approvals.
When properly installed, it is suitable for use under built-up, modified bitumen, and most single-ply roofing systems.
Advantages of PolyIso Insulation Board
High insulation value –– Excellent “LTTR” value compared to any other FM Class I rated products of equivalent thickness.
EPA compliant blowing agents containing no CFCs or HCFC; has zero ozone depletion potential and virtually no global warming potential. Excellent dimensional stability. High moisture resistance and no capillarity; is stable and maintains its physical and insulating characteristics.