In most cases, construction is characterised by at least three board layers arranged crosswise and by a load-bearing layer set up symmetrical to the centroid axis of the system. Cross laminated timber can, depending on the manufacturer, be constructed in up to 27 layers of which some may be glued together with parallel grain.
a) Crosswise formation of the layers b) Two parallel outer skins
Cross section of construction
The cross sections are manufactured using boards of at least sorting grade S7/C16 M. Outer skins are usually made of sorting grades S10/C24 M. The boards can be finger-jointed in the longitudinal direction. Depending on the manufacturer, they have board thicknesses of between 12 and 45 mm.
Individual layers can be made of derived timber boards such as OSB or parallel laminated veneer boards. Non-load-bearing outer skins can also be used for optical or fire protection reasons.
Element thicknesses of up to 300 mm (thicknesses of up to 500 mm are permitted depending on approval) are standard. Element widths are normally available up to 2.95 m (on request, and depending on manufacturer, up to 4.8 m, at lengths of up to 60 m (on request, and depending on manufacturer, up to 20 m). The use of narrower elements with system grid sizes of 62.5 cm up to 70 cm is also common.
Since individual manufacturers produce different standard thicknesses and widths, the precise dimensions should be taken from the manufacturer's product information at the planning stage.