How to design a low-level deck?

Gavin41

I want to build a Kwila deck measuring 3.0m x 2.5m .There is only 250cm from ground level to the surface of the deck. Can I use just one level of joists supported on galvanised stirrups and no bearers? What size timber should I use for the joists and how far apart should they be spaced?

Cheers, Gavin

Akanksha

A warm welcome to the Bunnings Workshop community, @Gavin41! We're delighted to have you join us and we look forward to assisting you with your home improvement and garden projects.

Thanks for your question on designing a low-level deck. This is a very popular topic among our community. Our resident D.I.Y. expert @EricL will be online later this afternoon and will be happy to assist with your questions. Also tagging @tom_builds, @Jimi, @DIY4Knuckleheds and @Dave-1 for their thoughts.

While waiting, can I request you to provide any photos of the outdoor area where you're planning on constructing your deck? This will help our members suggest more tailored advice suited to your specific needs.

In case you haven't already, I recommend reading experienced Workshop member @Adam_W's article on How to build a low-level deck and How to build a deck by D.I.Y. expert @MitchellMc for handy tips to get you started.

If you're after some project inspiration, you can also check out the Top 10 most most popular decking projects shared on Workshop as well as these inspiring low-level deck builds.

Let me know if you need a hand getting the most out of the site. I'd be happy to help.

Akanksha

Dave-1

Good Morning @Gavin41

Id like to say welcome as well It is an interesting place in here, so many ways of doing projects is one of teh things I enjoy.

Any chance of a couple of pics of the area you want to put the deck in? It helps to solidify what you are describing

You could I suppose do what you are asking, tho you would need more stirrups so the joists dont have a chance to even think of flexing.

I used stirupps/bearers and joists and have found that my deck dosnt flex a decade later so I kind of think that way. (I still need to post that project lol)

Depending on what the ground is like, damp/dry/water prone is another factor I am thinking of. Being so close to the ground it may change the type of timber you would want to use. I had my joists placed 550mm-600mm apart I t hink (thats a long time to think back) and I used recyled hardwood. I would suggest at least 45*90mm H3 timber for your deck. I would wait until the others get here tho as they have a lot more knowledge

Dave

EricL

Hello @Gavin41

Thanks for sharing your question about designing a low-level deck. The decking frame you are referring to is called a single layered structure. This type of framing is generally used in situations where the vertical space available is limited. For example, if you have a 250mm vertical space available you just need to subtract the timber frame and decking panel thickness you'll be using to get the available gap under your deck.

If for example, you use 90mmx45mm along with 19mm Kwila decking, it would leave you with a gap of 141mm underneath your deck to allow airflow to pass through. The commonly used spacing between joist is 450mm but can be adjusted depending on the circumstances of your build.

I strongly urge you to have a look at @MitchellMc's guide - How to build a deck. This is a fantastic example of how to build a decking frame and supporting it with foot pedestals.

My best advice before you start making any plans is to determine if the location you've chosen has adequate drainage. It's important that the soil underneath the deck does not hold standing water. Trapped moisture under your deck will accelerate its deterioration and it's important that any rainwater that goes under the deck gets drained away.

I propose drawing up a decking frame plan on paper or your favourite rendering software and sharing it with the community. You can also post any question you might have regarding the frame plan you've drawn up.

One other important reminder is to check with your local council regarding the rules and regulations regarding building a low-level deck near your home.

I also suggest having a look at the Bunnings video guide on how to build a low-level deck.

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

Eric