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How to build a deck of irregular shape?

Just Starting Out

How to build a deck of irregular shape?

Hello Helpful People,

I would like to build a deck but the area is of irregular shape. I have not undertaken any such tasks before so I am at a loss. I have attached a layout showing the footing layout made up of a grid of 100x100 timber posts. The regions circled in red are where I I will face problems. Can you please advise how may I support the load in those areas? 

I am a first timer. I would appreciate your patience. Let me know please if more information is needed. Thanks in advance. Deck Proejct.PNG

Bunnings Team Member
Bunnings Team Member


Welcome to the Bunnings Workshop community @NoClueButTrying. It's wonderful to have you join us, and many thanks for your question about deck layout.


The answer is adding more posts and running a joist between them down the diagonal edge of the deck. At the moment, your posts are too far apart. 450mm would be the max span for decking, so I've added the additional posts between yours and then along the edges. Now, you can lay your decking boards and have something to support their ends. In some cases, you can have a small counter-levered section at the edge of the deck where the joist can be unsupported, so this might save you from having to add the additional post in some sections.

Please let me know if you have any questions.


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