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Decking over concrete slab

Tracey113
Just Starting Out

Decking over concrete slab

Hi

 

we are looking to deck our alfresco area, its a concrete slab with a 70mm step down - not much I know, what’s the best way to go about it with such a small step down to work with ? 

 

2C672662-68EF-4550-8148-D90B08ECEE30.jpeg

 

does anyone also have a great program to work out deck plan / spacing etc ?

 

thanks heaps!

 

 

BIM_Engineer
Former Community Member

Re: decking over concrete slab

Read this

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Jason
Community Manager
Community Manager

Re: Decking over concrete slab

Hi @Tracey113 ,

 

Welcome to Workshop. We look forward to seeing how this project progresses and trust that you'll get plenty of helpful information and advice from our members. Feel free to post whenever you need a hand. 

 

I also welcome any feedback about how we might improve Workshop for you. Just let me know.

 

Thanks,

 

Jason

 

 

 

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asarson
Growing in Experience

Re: Decking over concrete slab

Mc Donald Jones Homes? I just built a deck over our concrete slab with "70mm" setdown. The main sliding door was even less than 70mm setdown, other bedroom door was more than 70mm, had plenty of issues getting it done, wall to the right was not square either. 

70x35mm Pine subframe secured to concrete with screws / plugs. Levelled using window packers

5mm spacing, wanted 5mm minimum which worked out good as the board widths over the width of the deck worked out full boards the whole way across. Painted the subframe black to avoid the "see through" effect. 

 

 

 

 

 

70x35 subframe secured to concrete using screws & plugs.70x35 subframe secured to concrete using screws & plugs.140mm Merbau decking with 5mm spacing.140mm Merbau decking with 5mm spacing.

Re: Decking over concrete slab

Hi, Just a thought. Did you put down a moisture protection layer between the frame and the decking boards?
If you do, then this normally comes in back, which means you would not have seen through the decking boards.

Cheers, Mark

 

Re: Decking over concrete slab

@asarson yes ours is MJH house - in hindsight wish we realised that the set down was only 70mm. Do you mind sharing a pic of what you did around the pillars and the edges / sides ?? 

asarson
Growing in Experience

Re: Decking over concrete slab

Hey Tracy, 

 

Well as I am building a built in bbq the outside edge of the deck is still unfinished however I plan to picture frame finish the edges. It’s a little difficult since we are using 140mm boards and I can’t get to a full board around the pillars without cutting one down.. I plan to just check in full boards around the corners of the pillars rather than cut down full lengths. Hope that makes sense.. the inner wall was out of square also so we had to taper one end down. Rear edgeRear edge

 

Side edgeSide edge

 

Deck off master bedroom to eventually connect alfresco deckDeck off master bedroom to eventually connect alfresco deck

 

Jason
Community Manager
Community Manager

Re: Decking over concrete slab

Hey @asarson,

 

Just wanted to extend an overdue but very warm welcome to the Workshop community. It was great to see you sharing your project and assisting Tracy. It sounds like you have a lot of knowledge and experience you can share with community members.

 

We look forward to reading more about your projects and plans. Please feel free to post whenever you need a hand with anything or have something to share.  And please let me know if you ever need assistance with getting the most from the Workshop site, or have any feedback about how we can improve Workshop for you.

 

All the best,

 

Jason

 

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Re: Decking over concrete slab

Hi Mark (@MPountley)

 

Many thanks for joining in the discussion on Workshop. Really sorry for the slow reply, but I did want to welcome you to the community. We are really looking forward to reading about your own projects. Feel free to post anytime. 

 

Thanks again,

 

Jason

 

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Re: Decking over concrete slab

Hi @asarson

Did you bolt the joists to the concrete at every 600 mm along the joists?

Thanks,

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