Celotex Thermaclass Cavity Wall 21

Thermaclass Cavity Wall 21 is a high-performance polyisocyanurate (PIR) insulation board specifically designed for full fill cavity wall applications. With an impressive thermal conductivity of 0.021 W/m.K, it provides exceptional thermal efficiency, helping to meet target U-values while minimising the required insulation thickness. Its low emissivity foil facing further enhances thermal performance, particularly in applications with a 10mm residual cavity.

The lightweight boards, measuring 1190 x 450mm with a convenient tongue-and-groove edge profile, are designed to fit standard cavity wall tie spacing. This makes them easy to handle, transport, and install, reducing on-site effort and speeding up the construction process. Whether used with a small residual cavity to account for mortar squeeze or as a true full fill solution with no residual space, Thermaclass Cavity Wall 21 ensures an effective and reliable fit.

Approved by the British Board of Agrément (BBA certificate 16/5343), this insulation board is recognised as fit for purpose in full fill cavity wall applications when installed in accordance with the certification guidelines. Its durable low emissivity foil facing not only improves thermal performance but also adds to the product's reliability and longevity.

Thermaclass Cavity Wall 21 combines exceptional thermal performance, ease of installation, and BBA-certified quality, making it a trusted choice for cavity wall insulation. It’s an ideal solution for projects requiring high performance with streamlined installation.