ThermalCavity 4mm Reflective Wall Cavity Insulation

Trade Select ThermalCavity™ is a purpose-built reflective wall cavity insulation delivering high performance in minimal space. Just 4 mm thick, it’s ideal for masonry walls, drained cavities, and tight wall voids, providing R0.11 thermal resistance and a Class 1 vapour barrier in one easy-to-install roll. The dual foil facings reflect radiant heat, reduce condensation risk, and help buildings in tropical and subtropical climates meet energy codes. Fibre-free, tear-resistant, and rated for all BAL fire zones, ThermalCavity™ enhances wall performance in both residential and commercial applications. Each roll covers 30 m² and installs easily during construction or retrofit, making it a preferred choice for builders needing space-efficient wall insulation. Product Specifications Thickness: 4 mm Material R-Value: R0.11 Emittance: 0.03 (foil side), 0.90 (anti-glare side) Vapour Classification: Class 1 Vapour Barrier Fire Classification: Low flammability | Suitable for all BAL zones Durability: Extra Heavy Duty Water Resistance: Water barrier UV Resistance: Up to 90 days exposure Dimensions Roll Size: 1350 mm × 22.25 m Coverage Per Roll: 30.04 m² Material Composition Core: Closed-cell cross-linked XPE foam Facers: Highly reflective foil on one side Anti-glare treated foil on the other Bonding: Heat-laminated foil/foam composite — fibre-free and safe to handle Best Uses & Applications Masonry Cavity Walls: Designed for double brick or brick veneer wall cavities where insulation depth is limited. Enhances R-value and reduces radiant heat transfer. Drained Cavity Systems: Works within narrow air gaps in cladding systems — ideal for residential or commercial buildings requiring a thermal break without bulk. Tropical & Hot Climates: Reduces external heat gain in brick structures — helps comply with energy efficiency standards in Climate Zones 1–3. Retrofit Wall Insulation: Can be inserted into existing cavities to upgrade thermal performance without major reconstruction. Bushfire Rated Buildings: Fully compliant for all BAL zones under NCC requirements.