Design of a low-density wood–cement particleboard for interior wall finish

Gypsum boards form a very large part of the building walls and ceilings finishing market. However, they have poor screw-withdrawal resistance, low hardness and are highly sensitive to moisture. The objective of this study was to determine whether it is possible to make wood–cement particleboards of the same density as gypsum boards while avoiding these drawbacks. Wood–cement particleboards were made by pouring the wood–cement paste in a mould. This was made possible by adding a viscosity modifying mixture to the mixing water and a set accelerating mixture to improve wood/cement compatibility. The mechanical properties and surface quality of the wood–cement particleboards were improved by using, on the board surfaces, paper sheets that were the same as those used on gypsum boards. The average specific gravity of the wood–cement particleboards was the same as gypsum boards, at 0.7. The average bending modulus of rupture obtained for the wood–cement particleboards was 10 MPa in the finishing paper principal direction and 5 MPa in the other direction compared to 5.5 MPa and 1.6 MPa respectively for gypsum boards. The average screw-withdrawal resistance of wood–cement particleboards was 570 N, that is, 1.7 times higher than for gypsum boards.