Strength classes
of glued laminated timber

According to DIN EN 14080, glued laminated timber is divided into different strength classes. During production, all lamellas are visually or mechanically sorted in order to assign them to a (tensile) strength class (criteria here are, for example, knots and annual ring width in the case of visual sorting and gross density and modulus of elasticity in the case of mechanical sorting). Furthermore, the finger joint of the lamellas determines the strength of the glued laminated timber.

Designation of the strength classes

The designation of the strength classes of glulam begins with the letters “GL” (glued laminated timber) and the following number indicates the bending strength. The letter at the end indicates whether the cross-section is homogeneous (h) or combined (c). Homogeneous glulam consists of lamellas of the same (tensile) strength class over the entire cross-section.

Strength classes for combined glulam

Combined glulam consists of lamellae of a higher strength in the edge areas of the cross-section than in the inner area. This layered structure is particularly useful for bending beams, as here the edge areas are subject to high tensile or compressive stress. This enables efficient use of the material.


Individual glulam

With our glued laminated timber (glulam), individual constructions can be built, because we produce the components in almost any shape and size – entirely according to your wishes. The kiln-dried wooden boards are joined together by finger-jointing to form long lamellas. Discover our wide range of glulam products.

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