In contrast with published information over the last 18 or so years ago the product industry has been receiving is not from a single species and virtually no grading standard applied to it.
This published information seems to be viewed as “because it is in print or on a website then it must be true”. There is a lot which could be said in this regard but enough to say for too long there has been more consideration of species and grading gone into someone building a pergola than industry has had supporting the mine roof.
The sawmills which produce for MTT all harvest only commercial species of structural hardwood (black butt, spotted gum, iron bark, flooded gum, messmate etc)
Each mill grades the sawn timber produced to AS 2082 – 2007 which is the Australian Standard for Hardwood Timber – Visually stress graded for structural purposes. We have adopted Structural Grade No.4 as the standard.
Further grading is undertaken when the actual element is produced in our production plant.
Consequently, by the time it is packed and wrapped it has gone through 2 grading processes.
Timber is timber so there are bound to be changes in it over time however unless we have some consistent guideline there is no chance of producing an element that can perform consistently and to a known level of loading.