Thermofoil™ Medium Duty Sarking Foil (733)

ThermofoilTM Medium Duty Foil is designed for use under both tiled and metal deck roofs in commercial applications and also as a wall system for domestic, industrial and commercial buildings.

ThermofoilTM Medium Duty Foil is a sarking foil consisting of kraft paper bonded in between two layers of aluminium foil with fire retardant adhesives. It also contains 13gsm fibre glass reinforcing yarn in between the two aluminium layers in a tri-directional pattern. Thermofoil 733 has a green anti-glare coating on one surface to reduce glare.


ThermofoilTM Medium Duty sarking acts as a waterproofing membrane and vapour barrier when installed beneath the primary roofing material, providing a secondary barrier against moisture, wind, heat, dust penetration and condensation control under metal deck roof. Thermofoil's integral thermal insulation properties also contribute to keeping homes warmer in winter and cooler in summer. 

Additionally, installation of Thermofoil Medium Duty sarking will add to the overall thermal performance of the roof and wall when a clear airspace of at least 20mm or more is provided at the reflective side of the foil face.

Thermofoil Medium Duty has a green anti-glare coating when installed to the outside of the building reduces reflection to acceptable levels.  Due to its unique construction, Thermofoil Medium Duty sarking has a medium water vapour transmission rate making it suitable for light weight wall cladding applications that are batten fixed, batten thereby providing the required air space of 20mm in between cladding and the Thermofoil.

Features and Benefits

  • Highly durable and easy to handle on large commercial sites
  • Excellent and cost effective thermal insulation
  • Provides ongoing physical protection against the elements
  • Reduces temperature variations and condensation inside the office, warehouse or your home
  • Increases energy efficiency; and
  • Improves comfort by weatherising your office, warehouse or home, minimising your greenhouse gas emissions


M2 per
Roll weight
1350 60 81 30