Extreme Subfloor Boards

Cem-Rock® eXtreme FLOOR represents a quantum shift in flooring technology and has been developed to rapidly improve flooring technology. Its fire, water, mould and mildew resistance properties far outweigh any competing products like plywood or OSB floor sheathing. It provides a superior flooring solution that is unaffected by environmental exposure during construction. is reducing the risk of fire, is not affected by adverse weather conditions, and drastically improves your building’s structural performance.


A1 Fire resistant

Unlike plywood, OSB or drywall boards.It can easily achieve up to 2 hour fire ratings

Water proof

Impervious to water Dimensionally stable when wet Structurally stable when wet

Sound Absorption

High density for great sound insulation

Reduced floor deflection

Great bending strenght

Technical Specifications

Property Value
Nominal dimensions
2400x1100x20 mm
Average weight
22 kg/m2
Average density
1100 kg/m3
Grey / White
Fire classification (BS EN 13501-1)
A1 (non-combustible)
Applications for joists @ 600mm c/c (BS EN 1991)
Category A, B, C1, C2, C4, C5 and D2
Fire resistance for timber joist buildup (BS EN 13501-2)
REI 45