Moisture Resistant (MR) Particleboard with its good water resistance and overlaid with melamine formaldehyde impregnated paper can make economic formwork which will give a smooth uniform concrete surface. The properties of Particleboard enables it to be used without regard to grain direction. This optimises the use of off cuts and avoids incorrect structural application.

The overlay is also an effective barrier against moisture ingress through board surface. Edge sealing will be required. The table below gives the spacing requirements of overlaid MR Particleboard for various concrete pressures and assuming three or more continuous spans with a deflection limit of span/270.

Maximum Spans for Concrete Formwork