Intended for partial fill insulation for masonry cavity walls, this Celotex CW4100 insulation board is a high-performance rigid polyisocyanurate (PIR). It included a 100mm thickness and is sized to fit between cavity wall ties across both new and existing builds as well as extensions. It has excellent thermal conductivity value of 0.022 W/mK and includes a low emissive aluminium foil facing to aid in obtaining impressive U-values, making this sturdy PIR board one of the best-performing options on the market while providing reliable long-term savings.CW4100 has been sized specifically to fit the standard wall tie spacing requirements. This means that you don't have to cut your board, allowing for installation that is easy and quick. As long as it's installed correctly, it can help meet carbon dioxide emissions and energy use targets set by the national building regulations. Features & Benefits: Celotex CW4100 Cavity Wall Insulation Board 1200mm x 450 x 100mm - 3.24m2 Pack, High-quality partial fill PIR insulation board, 3.24m pack coverage, Can be installed quickly and with low effort, Ideal for use in masonry cavity walls, Low emissivity foil facings that boost thermal insulation performance in cavity air spaces, 1200mm length x 450mm width x 100mm thickness, Compressive strength (kPa): CS(10\Y)120, R-Value of 4.50mK/W, 3.65kg/m maximum weightAdditionally, CW4100 comes with a BBA (British Board of Agrment) certificate so that you can confirm that it's designed to the highest industry standards. It even has BRE (Building Research Establishment) Green Guide Rating of A, so that you can improve your environmental performance substantially.Standards & Certification, Thermal conductivity: 0.022W/mK, according to BS EN 13165 for factory made rigid polyurethane foam (PU) product, Spread of flame: Euroclass F Reaction to Fire classification, according to BS EN 13501-1. Products with this level of classification are not provided with a rating for smoke emission., Certification: BBA certified, BRE Green Guide Rating: A for sustainability. Celotex CW4100 Cavity Wall Insulation Board 1200mm x 450 x 100mm - 3.24m2 Pack PIR