Products > Kooltherm > Kooltherm K15 Rainscreen Board > Overview Kooltherm K15 Rainscreen Board Insulation for rainscreen cladding systems Kingspan Kooltherm K15 Rainscreen Board Properties Download PDF Thermal conductivity (insulant thickness) 0.023 W/m.K (15-24 mm) 0.021 W/m.K (25–44 mm) 0.020 W/m.K (≥ 45 mm) Facings Composite foil Core Premium performance rigid thermoset modified resin insulant manufactured with a blowing agent that has zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP). Board size 1.2 x 2.4 m