Moisture sealing of floor slab

Only the basement floor slab is made of WU concrete. The walls are normal cast-in-place concrete and then designed as a black tank.

Then you have to seal it and you did everything right!

For us, only the basement floor slab is made of waterproof concrete. The walls are normal cast-in-place concrete and then constructed as a black tank.

Cast-in-place concrete is the execution of the basement! Even watertight steel fiber concrete with a thickness of 25cm is cast-in-place concrete.

Then you have to seal it and you did everything right!

I know.

Oh, believe me, a C20/25 concrete slab is not waterproof. It already seeps through from below. Or from the sides. Therefore a barrier.

Hi, quick question: If there is very clayey soil (almost no infiltration), does it make sense to use waterproof concrete for the floor slab or is the waterproofing membrane completely sufficient? I am panic-stricken about moisture damage. Best regards