A wood-based board, produced on the basis of phenol-formaldehyde resin as water resistant, for use in exterior conditions (according to PN-EN 636), meeting the requirements of 3 gluing class quality according to PN-EN 314-2, composed of glued plies of wood (outer and middle veneers), whereat the directions of fibre of adjacent plies are staggered by 90°. The aluminium core of 0,3 mm or 0,5mm thick is internally placed and it could be among layers of veneer, central or symmetrically relative to the center of the plywood.