How to extend a concrete slab for shed base?

[johammer]

Hi,

I have a concrete slab in my backyard that is approx 3m x 1.9m. 

There’s not too many sheds that would maximise that space so I was wondering if my could I add a row of pavers behind the slam just to give me a little more space?

the shed would then be anchored on 3 sides to the concert and 1 of the longer sides to pavers. 

how should I approach this? 

thanks

[EricL]

Hello @johammer 

Welcome to the Bunnings Workshop community. It's sensational to have you join us and thanks for sharing your question about your shed base.

If the pavers were an extension to be used as a step and the shed anchored properly to the slab, then I would say yes. But anchoring into pavers is not actually safe and shed manufacturers will always specify to anchor into concrete slabs. I propose building form work to the side that you wish to extend and install Rio bars to provide support and stiffness to the side that will be added. You then pour new concrete to extend your shed base. My best advice is to make sure that the soil base is solid and level before you begin.

If added properly the extension should stay in place and provide a good solid anchor unlike pavers that will move and shift should water enter its foundation.  

Here is a handy step-by-step guide: How to pour a concrete slab by @tom_builds.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let us know.

Eric

[Nailbag]

Hi @johammer 

I agree with @EricL that extended the concrete slab would be the best option. As @EricL also suggested, it's a matter of drilling holes in the extension side to insert rio bars half in half out in the centre of the existing slab. This ties the new to old. But it does required a pneumatic hammer drill in order to make that sized holes, which you can hire. Then use old timber to box out to the desired side for a depth of 100mm. Thats basically how I did the same job for a mate of mine for the same reason as yours.

Regards Nailbag

[johammer]

Thanks I’ll look into it and keep you posted as to my progress

[Dave-1]

Good Evening @johammer 

Welcome to the Bunnings community page Its a good place for questions like this and there have been a whole range to search through for various ways you could go forward

Any chance of a few photos showing your slab and shed? I must admit id be tempted to use pavers to extend the base of a shed a "little" more. With the knowledge that what @EricL and @Nailbag have both said is a wiser course to follow. 

Pavers = Cheap and resonably easy to do.

Pavers - Cannot seal the base from water.

Pavers - May sink or become unlevel

Pavers - Wont provide a secure option on that wall from windlift.

Its a matter of weighing up the benifits, the value whats in the shed and also where the shed could end up...

Whichever way you decide, make sure you provide somewhere water can run off to (drainage) and also what the water running down the side of the shed will do.

Dave