Laying concrete over existing concrete?

E D

5 years ago

last modified: 5 years ago

We’re having a small concrete patio installed in place of an old concrete slab.

The guys doing the work have left some of the old concrete and plan to pour the new concrete over it.

Is this possible? Or does all of the old concrete need to be taken out first?

In the photo It’s the bits adjacent the right hand wall.

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Comments (4)

Sonia
5 years ago
Can’t see any photos E D. However I’ve just texted my brother who is a builder and he says “ It depends how thick you put it on - it will need to be at least 4 inches thick and put steel mesh in, if not you have to take it up”. Hope this helps.
E D thanked Sonia
E D
Original Author
5 years ago
Thanks forza. Thusfar I haven’t been able to post photos. Maybe it’s the South American WiFi... :)

Will keep trying.

Coming back to the house just now they had already poured a new layer of concrete but assured me they took up all the old concrete. I can only take their word for it :)
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E D
Original Author
5 years ago
Above photo was meant for my first post.
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Sisabel
2 years ago
last modified: 2 years ago
I think pouring the new concrete over the old one may be a good idea to help you save money, but it is possible if the old one is not damaged or of poor quality. Probably some construction engineers could give you the best answer. I dare not make such decisions alone. We recently poured concrete on the front terrace of the house with the help of specialists from https://albatrossrestoration.ca/, and they informed us about the best solutions that would be convenient in terms of time and money.

Laying concrete over existing concrete?

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Sonia

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Laying concrete over existing concrete?

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Sonia

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