How to build a composite deck using Tuff blocks?

[Joicekocheri]

I am looking to build a deck as per the attached picture. Could you please advise me of the materiels needed and the spacing .

Planning to go with composite decking board and tuff block. Please advise. 

[JacobZ]

Hi @Joicekocheri,

A warm welcome to the Bunnings Workshop community and thank you for your question.

You'll want to start by checking your requirements in terms of building approval with your local council. Low-level decks are often exempt, but not in all areas, so it is certainly worth asking the question before proceeding to the planning stage.

You might like to start by having a look at the following articles - 

• How to understand deck components
   
• How to understand deck span tables
   
• How to build a low-level deck
   
• How to build a deck.

You'll have to consider the direction you want your decking boards to run as this will determine the layout of the frame beneath. I am happy to help with a design for your framing when you can let me know which way you'd like the decking boards to run.

Unfortunately, TuffBlocks won't work on the concrete area because of the height restriction. You will need to use a lower profile pedestal such as these Builders Edge 25-40mm Minifoot Pedestal Feet. By using these low-profile pedestal feet, you can use 140x45 H3 Framing Pine for your deck frame which allows your bearers to span 1400mm between pedestals and your joists to span 2600mm between joists.

For the stepped-down area, you can use the Tuffblocks with 90x90 posts to raise the height of the deck, so it is the same as the concreted area.

Here is a possible layout for your frame that would have the decking boards run parallel to the sliding door at the top of your diagram.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[Joicekocheri]

Hi Jacob, 

Thanks for the advice. I was planning to lay the decking board parallel to the sliding at the top of the diagram.

I will be very happy if you could help me with the design of subframe.

The finish hieght from concrete is 175mm

So the Minifoot 25+ 140 frame+ 23 deck board=188

Could you please help?

Thanks

Joice

[Joicekocheri]

I am also planing a picture frame

[MitchellMc]

Hi @Joicekocheri,

If your available height does not accommodate 140mm timber, then you'll need to use 90mm timber.  That way, the deck will have a finished height of 138mm, or you can increase the height of the deck up to 153mm with the pedestal at its max height of 40mm.

Regarding your sub-frame using 90mm timbers, you'll need to run your joists from left to right at 450mm centres.

Please let me know if you have any questions.

Mitchell

[Joicekocheri]

Hi Mitchell,

Tina's for the advice.

Is there any pedestal option that I can bring the height to 173mm?

Kind regards

Joice 

[MitchellMc]

Hi @Joicekocheri,

There is a range of pedestal feet of different sizes. To achieve your 173mm with 90mm joists and 23mm timber, you need a foot of 60mm in height. This Builders Edge 35 - 60mm Smallfoot Pedestal Feet at max height will accommodate that.

Mitchell

[Joicekocheri]

Hi Mitchell,

please advice if I am travelling in correct direction.

Planning to go with diagram proposed by Jacob

H3 pine 90x45

Planning for 5 bearers with joist span of 1400mm (total length is 6700mm)

bearer span at 900mm with small foot pedestal feet

For the stepped-down area, I will use the Tuffblocks with 90x90 post

Kind regards

Joice

[MitchellMc]

Hi @Joicekocheri,

Since you are going down in bearer size from 140 to 90mm, you'll need more of them. I've created a rendering below.

Joist span can't be further than 1000mm with 90 x 45mm. Supporting the bearers at 1000mm should be sufficient.

Mitchell

 

[Joicekocheri]

Thanks you