Abstract: In manufacturing fiberboard, it is known to press mixtures of lignocellulosic material and binding agents to form a board product. In this invention, an improved process for manufacturing fiberboard is disclosed including the step of adding a solution of maleic anhydride and glycerol to the lignocellulosic material prior to refining thereof. The binder used is preferably phenolic-formaldehyde resin, in which case post-heating may be beneficial.

Abstract: A siding panel formed from a body of hardboard material is formed with a locking tongue at or adjacent its upper edge and a locking seat at its lower edge. The locking tongue of one panel is arranged to be seated in the locking seat of another panel when adjacent panels are arranged with their marginal edge portions overlapping one another in use. The locking seat is in the form of a notch which is formed in the back face of the body of the panel. The notch extends upwardly from the lower edge and underlies the lower marginal edge portion of the panel.