Johns Manville AP™ Foil-Faced Polyiso Continuous Insulation board consists of a uniform closed-cell polyisocyanurate foam core bonded on each side to a foil facer. One side has a reflective foil facer and the other side has a white non-reflective foil facer to suit your building needs. Polyiso provides one of the highest R-values per inch of any rigid insulation (R-6.0 at 1 inch). Furthermore, when properly installed, AP Foil-Faced Polyiso Continuous Insulation functions as a water-resistive barrier, vapor barrier and air barrier, eliminating the need to install additional components. AP Foil-Faced Polyiso Continuous Insulation is produced with an EPA-compliant hydrocarbon-based blowing agent that has zero Ozone Depletion Potential (ODP) and virtually no Global Warming Potential (GWP). Polyiso is one of North America's most widely used insulation products and has been cited by the EPA for its responsible impact on the environment. AP Foil-Faced Polyiso Continuous Insulation provides exceptional heat, moisture and air control to protect your building's exterior wall assembly.