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.