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.

[Brad]

I am in the fix it down camp.

[Jithesh]

Thanks @Brad  and @MitchellMc . Goong with your advice, I have decided to dynabolt the frame down to concrete. What dynabolt can I use with carinya-heavy-duty-75-x-75-x-40-x-3-5mm-zinc-plated-angle-bracket_p0046917 and the drill bit for that please? I will use coach screw for the joist.

Is sleeve anchors recommended to use on concrete?

[MitchellMc]

Hi @Jithesh,

I believe Ramset 10 x 75mm Dynabolt Plus Hex Nut Bolts would be adequate for fixing the brackets down. Any sleeve anchor in those sizes would suit. A Sutton Tools 10 x 120mm SF TCT Masonry Drill Bit would be suitable for drilling into the concrete.

Please let me know if you have further questions.

Mitchell

[Jithesh]

Hi @MitchellMc . I have started the working on the frame and here is the progress photos. Will continue on the frame over weekend and hoping that the deck will be ready in couple of weekends. 

[MitchellMc]

Hi @Jithesh,

That's looking fantastic! Make sure you take plenty of images as you progress as I trust our members will be interested in following along.

Many thanks for sharing your update. Please let us know if you need any assistance.

Mitchell

[Jithesh]

Finally the deck is ready!!! It took 3 full weekends to complete it. Can't be more happier with the outcome. Now on to oiling part.

Question: Do I need to weather the deck or use Intergrain UltraPrep Tannin And Oil Remover  and the deck clean & apply the oil straight away? My son's birthday is coming and I am hoping to have a little party there.

[MitchellMc]

Hi @Jithesh,

That looks amazing! You should be very proud of your efforts.

For a new deck, you'll need to use the Intergrain UltraPrep Tannin And Oil Remover and once you have completed that process you then use Intergrain timber cleaner.  After the two products have been used to their specifications you can coat the deck once it has dried.

Congratulations on your result and please let me know if you have further questions.

Mitchell

[Ari]

@Jithesh  Thanks for sharing your plans and photos.  Your deck looks great.  I'm working up the courage to build a 5.7 x 5.2m low level deck over uneven pavers, and reading your posts was really helpful.  Thanks again.

[Jithesh]

Thanks @Ari . Glad that I that you found my post useful. Good luck on your project.

[MitchellMc]

Hi @Ari,

You might like to consider using Builders Edge Pedestal Feet as they are adjustable to suit your uneven pavers. 

Please let us know if you need any guidance with building your deck. We're here to help.

Mitchell