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How to add extra concrete to existing slab?

kaushikmistry
Finding My Feet

How to add extra concrete to existing slab?

Hello

 

I want to extend my outdoor concrete by 2m x 1m on the right side. Do I need to put expansion foam on the 2 sides ?

Any advice would be much appreciated.

 

Thank You

 

I have attached a picture 

1000011068.jpg

 

1000011069.jpg

JacobZ
Bunnings Team Member
Bunnings Team Member

Re: Adding a piece of extra concrete

Hi @kaushikmistry,

 

Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you join us.

 

Expansion foam, such as Abelflex, is a must if you are pouring a slab up against another slab without attaching it with the use of reinforcing dowels.

 

This is because the two concrete masses are not connected so they will move separately from each other. Expansion foam is a good way to stop cracking occurring due to this movement.

 

You might like to check out How To Pour A Small Concrete Slab and How to Extend Existing Concrete Driveway for some further information.

 

Let me know if you have any further questions.

 

Jacob

 

Re: Adding a piece of extra concrete

Hello Jacob,

Many thanks for the great advice.

I also wish to ask. The existing slab is 100mm in depth, how far should I dig the area to incorporate Compacted Road base.

I will have a mesh wire and shall be using mesh chairs.

 

Thanks

 

EricL
Bunnings Team Member
Bunnings Team Member

Re: Adding a piece of extra concrete

Hello @kaushikmistry 

 

If it is only being stood on and not driven over, I suggest a depth of 130mm. That should be enough space for the road base and the Reo mesh.

 

If you need further assistance, please let us know.

 

Eric

 

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Re: Adding a piece of extra concrete

That's great, thanks

 

yes it's only an extra piece in the back garden, of which I intend to eventually just put my large barbeque on it.

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