Low-level deck on concrete slab

Jithesh

Hello there. I was doing some research around DIY decking over concrete and stumbled across this forum. What a lovely thread. Many thanks for some of the tips here which I find very useful. I still have few questions in my mind which I am hopeful that the community here will be able to help me with some guidance in the right direction.

I'm planning to put a 7m X 4m deck over my concrete alfresco. I will be using a Merbau deck board and H3 treated pine for joist & bearers with joist placed every 450mm and bearers 2m apart.The maximum height for me to work with is 135mm. If I use 70x35mm T/P, the total working height of the deck board (19mm) + Joist (70mm) + bearer (35mm) will come to 124mm. That leaves me with 11mm for the spacers below bearer and for the flashing below deck board.

Q1. Will that spacing (~11mm) below bearer be enough?

Q2. Do I need to seal the concrete before putting the frame?

Q3. I'm not planning to attach the deck to the brick wall or to the concrete floor as there is a pillar in the middle which I am expecting to hold the deck in its place. Does that approach sound right?

Community manager's note: Check out How to build a low-level deck for expert advice.

BAditya

Hi Jitesh i am planning to do DIY decking need your support

EricL

Hello @BAditya

Welcome to the Bunnings Workshop community. It's wonderful to have you join us.

It's great to hear that @Jithesh's decking project has inspired you to build your own. Before you begin, I suggest having a look at these guides - How to build a low-level deck by @Adam_W and How to build a deck by @MitchellMc. These guides will give you ideas on what you'll need to consider while planning your deck.

My first suggestion is to measure the area you are planning to cover with your deck. Draw it on a piece of paper so that you'll have a general shape of the deck. I then propose thinking about which way the decking panels will be laid on the decking frame. Once you have an idea of the direction of the panels, you can start planning the frame underneath.

I recommend watching this deck building guide from Bunnings:

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

Eric

Jithesh

Hi @BAditya ,

Happy to help. You can refer the full post here and I have shared most details in the post or in the comments - https://www.workshop.bunnings.com.au/t5/Featured-Projects/Low-level-deck-with-picture-framing/ta-p/7...

Feel free to ask if you need any additional info.

Good luck.

BAditya

Hi All thank you very much for warm welcome. My decking project is exactly same size like Jithesh previous one. Only thing is i am thinking of using eco deck.

BAditya

Thanks @EricL i will start to draw project and soon share the image for assistance.

BAditya

Hi @EricL

i have just made a rough plan for my decking project. The height of sliding door from floor is 100mm. So what size timeber should i use? Also. i am looking to install eco deck the height of the eco deck is 23mm.

MitchellMc

Hi @BAditya,

You might like to start your own discussion on your project for more visibility and so our members can better assist with your questions. Just hit the red "Ask a question" button at the top of the page and include as much detail on your project as possible, including images of the area.

If the space you have to build your deck is 100mm and your decking takes up 23mm of it, then you are left with 77mm for the deck structure. This is not a lot of room to build a deck, and due to its low level, you can expect the early onset of decay and a premature life expectancy of the deck. The deck might be fine, but it's something to consider. You could use 70 x 45mm H3-treated timber for the joists.

Please let me know if you have any additional questions and I look forward to you starting a discussion on your project.

Mitchell