Ure-K is a thermal barrier approved as a building interior insulation to delay the ignition and reduce the surface burning rate of low melting, combustible rigid spray-on polyurethane foam. Ure-K may be sprayed over foam in existing buildings or it can be used as a protective coating over foam in new construction projects as a combination system. At the standard 1.25" thick application, Ure-K offers an NRC of .95 and an R-Value of 4.5.