Description
Thermaclass Cavity Wall 21 is a high-performance PIR insulation board designed for full-fill cavity wall applications. With an excellent thermal conductivity of 0.021 W/m·K, it delivers strong energy efficiency while keeping insulation thickness to a minimum.
Each lightweight board measures 1200 x 450mm and features a tongue and groove edge profile for a secure fit and straightforward installation. The low emissivity foil facing enhances thermal performance in sealed cavity air spaces, making it suitable for both full-fill installations and applications with up to a 10mm residual cavity to accommodate mortar squeeze.
BBA approved and manufactured to high standards, Thermaclass Cavity Wall 21 is easy to handle, quick to fit, and ensures reliable long-term performance.
Key Benefits
• Excellent thermal performance (λ = 0.021 W/m·K)
• Reduces insulation thickness required to meet target U-values
• Low emissivity foil facing for improved efficiency
• Lightweight and rigid – easy to transport, handle, and install
• Tongue and groove edge profile for a secure fit
• BBA approved
• Euroclass F reaction to fire (BS EN 13501-1)
Product Specifications
• Board size: 1200 x 450mm (installed dimensions)
• Edge profile: Tongue and groove
• Thermal conductivity: 0.021 W/m·K
• Fire classification: Euroclass F (BS EN 13501-1)