Ask An Expert

Home » Expert Advice » Ask An Expert

AS1684.2 mentions that strutting beams may be chamfered to a min of 100mm or 1/3 of their depth (whichever is greater). What are the design rules and methods for checking the minimum chamfer of other beams not obtained from the AS1684 tables. App E of AS1720.1 discusses notched beams, but I am specifically wondering about beams chamfered to fit under a sloping roof. Is it simply a case of checking the shear capacity of the reduced section at the face of the support? Can the App E method be applied to this case?

Woodsolutions Answer +

The limits set out in AS1684.2 apply to solid beams in general, including LVL. For example, Carter Holt Harvey’s literature specifies that chamfer cuts in their Hyspan product must not be less than 17.5 degrees or 1:3, with the remaining section not less than D/3 or 100 mm. Presumably other producers have the same requirement, although you may wish to check if you have a specific product in mind. Chamfer cuts to I-beams are as shown in Appendix J of AS 1684.2.


I am having trouble selecting equivalent strength rated GL beams and posts in lieu of F17 hardwood?

Woodsolutions Answer +

GL beams and posts produced to AS/NZS 1328 have a grade number that indicates their bending stiffness (modulus of elasticity), eg. GL8 grade has a stiffness (MOE) of 8GPa. If you have a design that calls for F17 timber you will need a GL grade with comparable stiffness properties. F17 timber has a characteristic stiffness value of 14GPa. There is no GL14 grade so you would need to go to the next higher grade which is GL17. Note that imported glulam may be graded differently, as explained on our website here: https://www.woodsolutions.com.au/blog/aus-vs-imported-glulam-markinglabelling.


I'm looking for Fire hazard test report from registered testing authority either Group 1, 2 or 3 rating for Tasmanian Oak (for internal cladding)

Woodsolutions Answer +

You will find fire test reports on our website here: https://www.woodsolutions.com.au/articles/fire-test-reports. The one you need is Report Number RIR 41117.7. Note that Tasmanian ‘oak’ is a trade name comprised of three species which are listed in the report under their individual names, mountain ash, alpine ash and messmate. However, they all fall into Material Group 3 in common with other tested species. It’s possible to achieve Material Group 2 rating by using a Tas oak veneer laid onto fire retardant treated MDF, designated FRMDF.

Sign up or Login to continue reading the answer.

Displaying 0/0

Show me 10 /20 /30

Haven't found what you're looking for?

If you have not found the answer for your question for in the Search results, please call the Expert Advice line or send us an email for a prompt response.



Call the WoodSolutions Expert Advice line on 1300 414 044*
Available Mon - Fri: 9am - 5pm

*Please note, there is a charge, determined by your telecommunications provider, for these calls.
This service is not available to international callers.

Are you looking for a supplier?

Social Media Feeds