Kalsi RigidBacker

Kalsi RigidBacker is a multi-use medium density fibre cement utilized predominately as a rigid wall underlay. Behind Kalsi RigidBacker is the experience and expertise of a Belgian group with its deep root in fibre cement technology, Etex, which specializes in manufacturing top quality building materials and providing various offers of sustainable and affordable solutions.

Kalsi fibre cement boards and planks are durable and highly resistant to most environmental conditions. They are the best alternative to wood, concrete and masonry constructions, as they meet the best performance required for dry construction solutions.

The autoclave technology has been perfected during the past decades to produce the best balance of quality and performance with many benefits in one single fibre cement building board.

Manufactured from a precise combination of cement, silica and cellulose, the boards are cured and stabilized in an autoclave – a special process involving steam, high temperature and pressure – that ensures optimum dimensional stability and mechanical performance.

Additionally the RigidBacker boasts an A1 non-combustibility rating when tested to fire testing method EN13501-1. This allows Kalsi RigidBacker on all projects up to and including P5 under the new MBIE guidance.


  • Resistant to the attack of insects and other vermin
  • Moist, mould and water resistant
  • Weather resistant
  • Impact resistant
  • Dimensionally stable


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