Glue-laminated timber structural grades in Europe are different than in Australia and the confusion between the two grading systems started from how they’re labelled. Both the Australian and European products label their glulam products using the GL’X’ descriptor, but it refers to different structural properties. Source: Timberbiz
The Australian building and construction industry uses a wide range of timber products manufactured in Australia as well as imported from all corners of the world.
Sometimes confusion may result in the Australian marketplace due to differing overseas product marking/labelling requirements; a potential for such confusion is the marking/labelling of structural glued laminated timber (glulam).
It has been reported that the availability of European structural glulam products in the Australian market may lead to confusion when simply looking at the marking/labelling of glulam products regarding the meaning of the numerical value in the GL“X” descriptor.
Both the Australian and European products mark/label structural glulam products using a GL prefix followed by a numeric ‘X’ value but refers to a different structural property in each product respectively, as follows:
- In the Australian/New Zealand (AS/NZS) system, the “X” refers to the bending stiffness(modulus of elasticity) in gigapascals (GPa)
- In the European (EN) system, the “X” refers to the bending strengthin megapascals (MPa)
To illustrate this difference in approach, Table 1 shows a “relabelling” of AS/NZS grades using the EN method and Table 2 shows a selective comparison between AS/NZS and EN grades in terms of their respective bending strength (f’b) and stiffness (E) (modulus of elasticity) values.
Table 1: GL Grade Comparison
Table 2: Strength and Stiffness Comparison
To learn more about these labeling comparisons, head to www.woodsolutions.com.au/blog/aus-vs-imported-glulam-markinglabelling