In 1989, following a meeting in Melbourne at the Chisholm Institute of Technology, the Glued Laminated Timber Association of Australia (GLTAA) was formed by the majority of Glulam manufacturers in Australia. It was clear that the timber codes in use in Australia and New Zealand at the time did not clearly define Glulam and its grades and properties. In fact, the standard for the manufacture of glulam, AS1328 was also inadequate in many ways and required redrafting.
The new Association adopted the following objectives which have under pinned the group from its inception.
A complete quality system was developed for all producers and importer members as a model. Each plant and importer has an obligation to develop their own in-house Q.A. process in line with the requirements of a third party certification and auditing body.
Each member in this category has a two year time frame in which to
- Develop their system
- Undertake qualification, monitored by an accreditation body. (GLTAA Inspectorate)
- Achieve full accreditation.
After receiving full accreditation they must
- Maintain the Q.A. system
- Review the system periodically
- Be subject to the third party audits conducted by the Inspectorate
The association faced several issues regarding manufacture of the product and design in the field and these had to be addressed by undertaking scientific research. For example:
- Long term creep in timber products has been established world wide and is used to predict deflection in timber under load. There was no established criteria in Australia for Glulam as a generic product and creep factors applied to solid timber in small sections were being used. This was detrimental to Glulam acceptance in Australia because in North America and Europe, the major markets for Glulam, a lesser creep factor was used.
- When AS1720 – 1997 was issued, the capacity factors published for Glulam was lower than other engineered wood products. A research project to clearly establish the capacity factors of Glulam was undertaken by Monash University for the FWPRDC and completed in 2003. It also has an objective to substantiate the values of the GL grades adopted in AS1720 – 1997.The conclusions of this study showed the capacity factor can be increased and this will be incorporated in the revision of the standard. It also concluded the properties of the GL grades in AS1720 can be amended upwards in some engineering properties.
- Current research (2004) is planned to establish design values on epoxy dowel joints, a project which has benefits world wide.
The redrafting of AS1328 – 1987 was an initiative of the GLTAA. The inadequacy of the standard became apparent to the group when the QA system was being formulated and the GLTAA sought representation on the standards committee responsible (TM-004). The input from the GLTAA assisted in the re-drafting of the finger joint standard, the Glulam standard and the creation of the non-structural glulam standard. The committees work for 2004 is:
- A new non-structural finger joint standard
- Redraft of the structural finger joint standard
- A standard on assessment of adhesives for structural purposes.
Through connections with members of the relevant I.S.O. standards committees, the work of the Standards Australia TM-004 committee is influencing world standards through connections with I.S.O. standards.
Generic Technical Information
As a part of the GLTAA’s objectives to provide the design profession with valuable information on Glulam, generic technical information on Glulam has been published by the association. These are available for download on this site in the form of data files.
Education on timber engineering for engineered wood products (EWP) in Universities for engineering students is vital for the next generation of engineers if the use of Glulam is to expand.
The GLTAA and individual members have provided test material and projects to various Universities in Australia to further that objective.
The GLTAA has an objective to promote the use of Glulam. The GLTAA quality mark is branding on products which has the backing of the GLTAA and it is “the Mark” which means users and designers can rely on the product with that mark.
A number of factors influence the choice of building materials, including cost, suitability and the design knowledge of those materials. Issues such as renewability of resources, energy efficiency and environmental friendliness are also becoming increasingly important and for environmentally conscious designers, glulam is a primary choice structural material.
Glulam is a natural structural material which is lighter to handle than the alternatives, has intrinsic beauty, is machinable in most cases on site and is totally biodegradable.
There has been substantial research into glulam over the past three decades and it is now accepted world-wide as a structural material of known behavioural properties.
Furthermore, there are other advantages in using glulam as a primary material. Timber is non-corrosive. In a fire, glulam has an inherent fire rating and glulam is easy to work with. Most importantly, as a finished, in-place structural material, glulam is cost competitive with structural steel.
When exposed, a glulam structure adds warmth and beauty to a building and unlike most other structural building materials, glulam is commonly used as the finished product.
The current GLTAA membership list and company profiles appear here.