It is the progenitor of all structural timber materials. Obtained by simply sawing the trunk, solid timber retains the visual and material authenticity of the plant, but requires care to accommodate its natural hygroscopic movements.
The strength of a solid timber beam is determined visually or by acoustic machines. To limit natural shrinkage cracking, modern technique favours free-of-heart cutting: the beam is obtained by removing the central pith of the trunk, the most unstable zone, subject to radial stresses during seasoning.
To overcome the dimensional limits of the trunk and the deformations of fresh timber, modern engineering introduced KVH (Konstruktionsvollholz): solid timber kiln-dried artificially to 15% moisture, planed, chamfered and finger-jointed longitudinally. This process turns traditional solid timber into a standardised, stable product available in lengths up to 13 metres.
Standards
European and international references applicable.
Physical properties
Usage environment
Must be installed at the equilibrium moisture content of the finished building. KVH dried to 15% inhibits fungi and wood-boring insects. Off-centre cut reduces radial stresses during seasoning.