A gypsum fibre board is a reinforced material consisting of gypsum and cellulose fibres. These two raw materials are mixed and after the addition of water (no other binding agents) they are pressed under high pressure to form panel sheets. Subsequent to drying, the panels are impregnated with a hydrophobic agent and cut into the desired sizes. With the exception of exterior applications, gypsum fibre boards can be used in all areas of dry wall and timber construction as panelling and lining in walls, ceilings, vaulted ceilings and floors. Gypsum fibreboards are inflammable and are classified A1 or A2 according to EN 13501-2.