Concrete Slab - Is this acceptable?

[CJRatch]

Hi guys,

Thanks for your time.

Currently having a kitchen extension built 6m x 4m. Builder just recently poured the concrete slab. Before he did building control passed the insulation etc and away they went. As far as I was aware the usual process is 4" concrete with steel followed by 2" screed however my builder poured 2" concrete (Ontop of 100mm Celotex and waterproof membrane) from a concrete wagon and mixed the second 2" himself using sharp sand and cement and added this ontop of the 2" of poured concrete, he said he kept the concrete wet all day while he added the cement and sharp sand and added steel at 2". He says this will save money on adding a floor screed at a later date to further level the floor as he's gotten it pretty level already.

Is this an acceptable process do you feel? He says as it was all done in one day and the concrete was kept wet it will have cured as a 4" slab?

Any opinions would be appreciated.

Thanks.

 

[tomfe]

6x4 x0.05 = 1.2 m3 he could have saved even more money by mixing it himself.
Was the 2" top dry like a screed mix or was it wet like a concrete mix?

I have never heard this done before, if building control had seen it they would not have passed it, 2" of concrete + 2" screed does not have the same strength as 4" of concrete as you know.
In the real world will it work, for the amount of money saved and the problems it could cause, I would not have done it but it might just work. I know not helpful at all.

 

[noseall]

Sounds like he's added time not saved it. Ridiculous concept. Has he married the new screed into the existing kitchen floor?

 

[CJRatch]

Hi guys, thanks for the reply's you have confirmed my frustrations.

The top 2" was mixed wet not like a screed mix will that give it more structural integrity as such? The extension floor is not an extension of the kitchen per say rather a separate room we will be using as a kitchen so the floor did not need to flow into another room. With last nights rain (The first since he did it) the even more frustrating part is it seems like he will have to use self leveling compound anyway as there were several large puddles, sigh.

Sigh it's been done now I know and the builder comes recommended I don't want to strain the relationship by questioning his work etc in your opinion guys will this last the test of time, 2" concrete, steel and then 2" wet cement and sharp sand all done in the same day?

Thanks again for your time.