How to build timber deck for front yard?

Question

Hi Mate,

I’m looking to install a small timber deck in the space at front yard (currently grass/soil). Image: attached in this message.

Before I go down the full custom‑build path , I wanted to check whether any ready‑made or modular decking systems are available through Bunnings.

I’m mainly interested in:

• Pre‑assembled decking

• Modular click‑together deck systems

Alternatively, custom design and assembly is considered.

Measurement: estimate

3m x 1.5m Height: 11cm

I wish long lasting timber like hybrid products or timber that last last longer within minimum maintenance.

Appreciate your thoughts on above.

Thanks

MM

EricL · Answer

Hello @nagumuthu

The proposed pebble gap is more than generous, and I don't see anything wrong with providing a 750mm gap between the deck and the wall. In regard to your second question, I suggest having a look at this featured discussion - Low-level composite deck over concrete and soil by @oninpena. It's an excellent example of a single layer deck frame that uses both angle brackets and pedestals. The deck is free standing and does not need to be anchored to the house or any other construct in your garden.

If you were to assemble it as a single layer decking frame it would be:

*

https://www.bunnings.com.au/brighton-masonry-300-x-300-x-40mm-charcoal-mypave-334-paver_p3451556

*

https://www.bunnings.com.au/builders-edge-35-60mm-smallfoot-pedestal-feet_p2450074

*

https://www.bunnings.com.au/90-x-45mm-outdoor-framing-h3-treated-pine-2-4m_p8032172

You would in theory have 40mm (paver) + 60mm (pedestal) + 90mm (timber framing). If you add the thickness of the deck panels which is 26mm you would end up with 216mm. But keep in mind that the pedestals height can be lowered or adjusted all the way down to 35mm thickness. Please note that the soil will need to be compacted to prevent movement.

I also suggest having a look at these guides - How to build a low-level deck and How to build a deck.

Here is a link for ideas and inspiration: Top 10 most popular deck projects

I also suggest having a look at the Bunnings video guide on deck building:

* How to plan out your deck  
* How to set out a deck 
* How to install stumps 
* How to install bearers 
* How to install joists 
* How to lay decking 
* How to add a step to your deck.

If you have any other questions we can help with, please let us know.

Eric

nagumuthu · Answer

Hi @JacobZ

Thank you for the detailed advice.

I plan to move the deck forward and leave a 75 mm wide strip of 40 mm decorative pebbles between the wall and the deck. This keeps all weep holes visible and accessible for inspection.

Question 1:

Is a 75 mm pebble strip between the wall and the deck considered acceptable, or is it unnecessarily large? My intention is to keep the weep holes visible while providing drainage and inspection access.

Question 2:

Could you please confirm whether I have understood the layer build-up correctly from top to bottom? Is pedestals necessary for the low deck build?

Should above table include the 'Bearer or Ledger' as well?

Question 3:

My site measurements are:

Natural ground to bottom of weep holes = 120 mm

Natural ground to top of alfresco tiles = 140 mm

Ideally, I would like the finished deck surface to be level with the alfresco tiles.

Based on the layers table above, the total height of the deck from natural ground to deck top is 208mm (excluding pedestal) and it appears I may need to excavate approximately 88 mm to build the deck in above layers.

Would you recommend:

Excavating the entire 3.0 m × 1.5 m deck footprint; or Excavating only beneath the pavers/support locations?

Thanks

NM

JacobZ · Answer

Hi @nagumuthu,

As a deck has gaps between the timber for water to drain, you can build it up to the underside, but not above the height of the dampcourse, which is the horizontal line beneath your weep holes. You'll also want to ensure there is a 3-5mm gap between the decking and the wall so any water that runs down the wall can pass between it to the ground beneath.

Beneath that decking, you would then have a frame and levelling feet, which will place the soil at least 100mm down from the bottom of the dampcourse, which is compliant with the 75mm recommended in the National Construction Code

https://ncc.abcb.gov.au/editions/ncc-2022/adopted/housing-provisions/5-masonry/part-57-weatherproofing-masonry

as long as the ground is landscaped with a slope away from the building.

You'll want to prepare the ground so that it has a slope away from the house. The NCC

https://ncc.abcb.gov.au/editions/ncc-2022/adopted/housing-provisions/3-site-preparation/part-33-drainage

recommends between 25-50mm of fall per meter within the first metre of the slab depending on the intensity of rain in your area.

Laying down geotextile can help to suppress weeds and stabilise the surface, so it is worthwhile to include. It can sit beneath pebbles; however I am not entirely sure where you are planning on having these pebbles. Could you clarify this for me?

Assuming the pavers are going to be sitting underneath the feet that are supporting your deck frame, then I would suggest a well compacted 100mm layer of crusher dust or road base. This will help to distribute the weight of the deck and support it well long term.

I hope this answers your questions and I am happy to help with any further that you might have.

Jacob