Glued laminated timber
Glued laminated timber (Glulam, BSH) is an industrially manufactured construction product for load-bearing constructions. It is made of slat boards that are laterally finger-jointed and then glued to each other with parallel grain. Thus glued laminated timber offers a great advantage as a construction product in comparison to solid beams: On the one hand, the load-capacity is larger than with solid wood, as imperfections (branches, etc.) can be cut out in advance, and gluing creates a homogenous cross-section. On the other hand, finger-jointing allows larger beam lengths. This means that span widths for roof-beams can be implemented up to 60 m without support. BSH glue connections must be made extremely carefully.
Glued laminated timber is produced as a standard or short-term delivery good in any desired length and dimension. Special construction parts are available, too, that exceed standard measures, and also shapes, such as higher raised beams, monopitch roof girders, arch girders, and free shapes. Roof elements can also be created out of glued laminated timber.
Glued laminated timber has become a sophisticated universally usable product in wood construction. Globally around 7-8 million square metres of beams are produced. Main production countries are Japan, Austria and Germany. At a distance, USA, Russia and Finland are next in line. The best known producers are, among others, Mayr-Meinhoff, Hasslacher, Binderholz, Stora Enso, and Chugoku Mokuzai. Larger span widths are produced by companies such as WiesnerHager and Derix.
BSH consists of board slats, just like BSP, and is technically dried to a certain wood moisture level. Typical construction timber is used, i.e. conifers, such as spruce, pine, larch or douglas fir. In rare cases, deciduous timber is used.