New kitchen extension concrete floor

[norahclare]

I have a very tiny kitchen in a 1930s end of terrace and I'm planning to have an extension built on to lengthen it and then build out widthways too, to extend the main house.
Under the lino in the kitchen is the original tiled floor- same as in the hallway. My builder says this has to come up and be replaced with a concrete floor so it matches with the extension. He did give a structural reason why they had to be the same but it went a little over my head.

Does this really need to happen?

I plan to floor the whole area including the original kitchen with ceramic tiles.

 

[Steve]

Chances are, those tiles are straight onto soil. I've seen this before, with screed applied over the top. The damp just eats through the screed and it falls apart. It needs to come up, and dug out to give a reliable foundation. You could try taking a tile up and having a look.

 

[norahclare]

Thanks I think that's kind of what the builder said so i'll go alond with that.