Magnum Board is a technologically advanced, high-quality Magnesium Oxide Board providing superior performance in the Flooring Underlay category.

  • Vapour permeable
  • Free of nasty chemicals
  • High moisture resistance
  • High impact resistance
  • Non-combustible with zero flame spread
  • Mould and insect proof
  • CO2 negative
  • Excellent adhesion
  • Installer friendly
  • Supported by independent test data
  • Suitable for use in Foreverbreathe™ Specification
  • Approved for internal and external application

Size Available

Ergonomic size 2.7m x 0.6m x 18mm T&G edge sheet for ease of installation over 450mm joist spacing’s.

Ensure your next build is healthy, sustainable and cost effective. Choose Magnum Board.®

Framing Guidelines

  • Magnum Board Flooring Underlay can be fixed to steel or timber joists at 450mm centres
  • Construction of timber framing must be in accordance with local building codes for timber framed buildings.
  • Construction of steel framing must be in accordance with local building codes for steel framed buildings.
  • Must be fully supported by level joists to square edges and T&G edges at joist positions - refer to technical manual.


Magnum Board Flooring Underlay must be fitted using a staggered layout. Where interior or exterior waterproofing is required, refer to technical manual.


Contact Form


John Carroll

Mobile: 0414301515

Colin Carroll

Mobile: 0421273887

Office Numbers

Phone: 1300233707