Calcium Silicate Boards

Rigid calcium silicate boards for fire-resistant and thermal insulation, classification up to 1100°C

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Calcium silicate boards are specified wherever a rigid, non-combustible material has to take mechanical load and hold its shape under hot, demanding conditions. Common roles include fire-rated doors and partitions, back-up insulation in industrial furnaces and dryers, flame holders and furnace baseplates, aluminium casting launders, and durable insulation in melting and holding furnace bodies. In petrochemical plants, cement works and domestic combustion appliances they act as economical back-up boards behind heavier refractory layers.

The substrate is hydrated calcium silicate reinforced with silicate fibres, which keeps it sawable, drillable and millable with standard tooling. Two widely used grades are KS-CaSi225 (225 kg/m³, 1000°C classification) and KS-CaSi245 (245 kg/m³, 1100°C classification). The material is stable against reducing protective gases such as hydrogen, carbon monoxide, methane, ammonia and nitrogen. When combined with castable refractories, a hydrophobic primer is recommended because the board is capillary-active.