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Decking Construction - Structural Timber Inquiry

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Decking Construction - Structural Timber Inquiry

Hi all,

Please forgive if someone already inquired about this, but I could not find any suggestions hence I post this query.

I am constructing a timber deck. For the timber stumps (as building permit required), I need 100mmx100mm H5TP stumps. But I even very hard to find a supply for this item. 

Is there any one here in the group know or refer where I can get H5 treated pine stumps?

I am in Melbourne - VIC.

Thank you and highly appreciated for your recommendations.




Bunnings Team Member
Bunnings Team Member

Re: Decking Construction - Structural Timber Inquiry

Welcome to the Bunnings Workshop community Eric (@dbmgardens). It's fantastic to have you join us and many thanks for your question.


I'm made contact with our timber supplier in VIC for treated pine and it appears a structural grade H5 100 x 100mm post is not available. They do have non-structural posts which we can order but given they are for deck stumps I do not believe they would be suitable.


I would assume the requirement for H5 is because you are concreting them directly into the ground. This could be mitigated by having a Pryda 300 x 90mm M10 Full Stirrup Solid Stem Post Anchor installed in a concrete footer. A 90 x 90mm 2.4m CCA Treated Pine Post could then be fixed into the post anchor. You would need to investigate the reasoning for the H5 requirement and whether having them not directly in the ground would be a solution.


Was there any option given for utilising concrete or steel posts?




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