As a high performance insulation board featuring low emissivity foil facings CW4000 offers enhanced thermal performance in cavity air spaces compared to typical PIR products. It’s these enhanced features that deliver thinner solutions to meet popular target U-values. With Celotex CW4000 you are specifying an insulation board that: Offers high performance insulation with low emissivity foil facings offering enhanced thermal performance within cavity air spaces Achieves an A+ rating when compared to the BRE Green Guide Is certified under BBA certificate number 94/3080 Is available as a BIM object Has zero ozone depletion potential (zero ODP) & low global warming potential (GWP) Future proofs the energy performance of new & existing buildings