Technical regulations

Technical approval Z-9.1-679	Glued laminated timber made of beech and hybrid beams made of beech/spruce
DIN 4074-1: 2003-06	Strength grading of wood - Part 1: Coniferous sawn timbe
DIN 4074-5: 2003-06	Strength grading of wood - Part 5: Sawn hard wood
DIN 1052: 2008-12	Design of timber structures - General rules and rules for building. DIN EN 1995-1-1 Eurocode 5: Design of timber structures - Part 1-1: General- Commonrules and rules for buildings. DIN En 1995-1-1 National Annex to DIN EN 1995-1-1
DIN EN 385: 2007-11	Finger jointed structural timber - Performance requirements and minimum production requirements
DIN EN 391: 2002-04	Glued laminated timber - Delamination test of glue lines

Cross-sections of laminations and beam lay-up

Cross-sectional dimensions for beech-laminations shall not exceed b x h= 150 x 30 mm, and for spruce laminations shall not exceed b x h = 150 x 42 mm.

The height of a glued laminated timber member made of beech shall not exceed 600 mm, and the height of a glued laminated timber beechwood hybrid beam shall not exceed 900 mm. The permissible width is 150 mm for each case.

The cross-sectional beam lay-up may be homogenous (characterised by the abbreviation h behind the strength class) or combined (characterised by the abbreviation c behind the strength class). In the case of a combined cross-sectional lay-up, the outermost laminations having the lamination strength class shall comprise at least 1/6 of the beam height H on each side, and at least two laminations.

The requirements on the strength of the laminations and the finger joints, depending on the cross-sectional lay-up, shall be taken from technical approval Z-9.1-679.