Piece in which the length and width predominate over the thickness, and in --which the main constituent element is wood. It is also known as a by-product of wood. There are different types of boards: - plywood board; - fiberboard; - particle board (chipboard and chipboard). In the wooden structures, of the previous boards, only those are used which, in the corresponding UNE standards, are specified for structural use or high structural performance. (The latter with properties of strength and rigidity greater than the structural analog).