Medium-density fiberboard is an engineered wood product formed by breaking down softwood into wood fibers, combining it with wax and a resin binder, and forming panels by applying high temperature and pressure.

From stock it is available in the following sizes:
2440 x 1220mm in eight thicknesses from 2mm to 25mm.
2440 x 1220mm - Moisture Resistant in three thicknesses from 12mm to 25mm.
3050 x 1220mm - Moisture Resistant in 18mm and 25mm.

Some varieties are less expensive than many natural woods
Isotropic (no grain), so no tendency to split
Consistent in strength and size
Flexible. Can be used for curved walls or surfaces.
Shapes well.

Heavier than plywood or chipboard (the resins are heavy)
Swells and breaks when waterlogged
May warp or expand if not sealed
Contains urea-formaldehyde which may cause eye and lung irritation when cutting and sanding
Dulls blades more quickly than many woods
Though it doesn't have a grain in the plane of the board, it does have one into the board. Screwing into the edge of a board will generally cause it to split in a fashion similar to delaminating.
Subject to significant shrinkage in low humidity environments.

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