Firstly, thanks for giving me the confidence to tackle my decking project. With too much time on my hands at the moment the advice and support on this forum has inspired me to tackle this long wanted addition.
The ongoing message is obviously plan, plan, plan ! And with that in mind can I ask some advice on my attached sketch -
To kick off , if there are any glaring mistakes with my plan, please let me know!
Once the frame is complete I intend to use Ekodecking as this is a rental property I need as little ongoing maintenance issues as possible.
With all the advice I’ve taken on board, I plan to utilise the two concrete slab areas and attach the joists with ‘L’ bkts and spacers.
Q1 - what size joists should I use and what spacing between them? I’ve worked on 450mm.
Moving from the patio onto the soil area I planned to concrete supports into the ground to support the cross bearers
Q2 - what size bearers and what spacing between them? I’ve worked on 750mm.
Once I’ve got those materials and info. locked in I can fine tune the plan.
Welcome to the Bunnings Workshop community. It's wonderful to have you join us, and thank you for sharing your question about your decking project.
It's fantastic that the low-level deck projects our members have made have inspired you to make your own. One way to determine the size of timber you can use is to measure the vertical space you have. If the deck is meeting up with your door, how much space do you have between the bottom of the door to the floor? For example, if the gap is 200mm you take away the thickness of the decking panel 23mm leaving you with 177mm. If we were to use 90 x 45 framing that would leave us an 87mm gap. On the condition that this is a single-layered structure.
However, if parts of your deck are going to be built as a standard deck structure then you would need more space. Would it be possible for you to post a photo of the actual area where you will be building your deck? This will give our members a better idea of its layout. We'll then be able to give you a more comprehensive suggestion. Another method of building your frame is to build your frame in sections rather than as a single whole. This makes for easier assembly and a much more rigid structure. I suggest reading this excellent guide - How to build a low-level deck by @Adam_W to give you more ideas on how to build your deck.
Here is a link to give you ideas and inspiration: Inspiring low-level deck builds
Here are some fantastic low-level decks our Workshop members have shared.
We look forward to seeing your photos.
Thanks for your response.
Although I’m not at the house at the moment, here are a couple of pics that I have on file.
FYI - the tree, plants and old sleepers have been removed in preparation for the deck.
The distance between the house door and the patio slab is 1250mm .
You’ll notice that the garden is pretty level with a drop of about 1400mm from the slab to the garden area.
I had certainly considered the Modular Decking as it looked super user friendly - I just wanted to ensure it was cost effective compared with buying lengths of timber, and could be used with the support posts I will need to concrete in.
I can send more detailed pics in the coming days if needed.
I've placed a picture to indicate the gap that I was referring to in my last recommendation. This gap will determine if it will be possible to build a low-level deck on the cemented patio area. When you get a chance to go to the property, please measure this gap and the height of the cemented area.
If you need further assistance, please let us know.
I’m confident that the gap you’ve indicated is 1250mm but will confirm once I’ve double checked.
Yep, the distance between the concrete slab is 1250mm.
1500mm to the bottom of the door frame.
I apologise for the delay in my reply.
I believe @EricL's confusion might be due to your measurements being slightly off. They should be 125mm and 150mm. You've got an extra zero in there.
With that amount of room, you'll be building a single layer deck, and 90 x 45mm outdoor treated framing timber would be suitable for the joists. It's what most of our members use in these tight situations. Our members also typically work with a 450mm spacing for joists. With 90mm for the framing timber and 23mm for the decking, that leaves you with 12mm for water drainage and airflow under the frame. In Eric's image above, you'll see that the framing timber is then attached to the concrete slabs with angle brackets, and plastic shims can be used to keep the spacing uniform.
Once the deck frame leaves the concrete slab, it doesn't look like you'll have enough room for a joist over bearer frame. You'll likely need to support the joists individually unless you're going to excavate a substantial amount of soil. Compacting the ground and placing pedestal feet on concrete pavers could be an option.
Please let us know if you have further questions.
Thanks for your response and apologies for the typo and confusion in my measurements - of course I meant 150mm 🙄!
Your advice is very clear and I’m confident and excited to get started.
Just a couple of questions regarding the frame leaving the patio slab. I would prefer more permanent supports rather than the pedestal feet and pavers.
So, with that in mind, if I was to individually support each joist would you suggest concreting supports into the ground, and if so, how many on each joist along the 2250mm span from the slab?
Secondly, if I did decide to use an over bearer frame, what depth would I need to achieve , using what size bearer?
I,m looking forward to getting started
You generally wouldn't consider a joist of bearer frame when working that close to soil @GaryL. In your circumstance, you'd need to remove up to 300mm of soil for clearance and then lay a layer of gravel for drainage. The minimum size bearer you could possibly use would be 90 x 45mm.
Instead of having the bearers, you could have supports at the 1125m mark and then again at the 2250mm mark. The joists can have their ends connected to a length of timber running perpendicular tying them together.
Awesome @MitchellMc ,
I’ll go with the individual supports.
Would you suggest using the Pydra Post Anchors ?