ᐅ Sloped recess in the foundation slab for a walk-in (curbless) shower

Hello.

While visiting some shell construction sites recently, I noticed the structure shown in the attached pictures.

A sloping recess about 20cm (8 inches) wide was included in the concrete slab, extending all the way to the precast concrete ceiling.

Of course, this is not my project, and theoretically it’s none of my business, but I’m curious if anyone has seen something like this before, and what kind of shower design would require such a construction, in case I ever need it myself…

The screed has not yet been installed, only the precast ceiling and the concrete above it. The interior and exterior walls have been built with masonry.

Best regards and thanks!

I mean, it looked quite similar for us as well, just straight. The water flow has to go somewhere, depending on where the drain is located and it also needs a slight slope. For us, the drain is positioned in the center of the walk-in shower tray.

As far as I know, there are no recesses in the concrete except possibly in a corner for the drainage pipe.

So far, I have only seen the preparation with a 50mm (2 inches) plastic pipe within the screed.

I have some doubts about whether it’s acceptable for the reinforcement to be visible. It also looks more like a mezzanine floor than a slab foundation. Ideally, for the slab foundation, a PVC drain pipe should be laid in the correct position below the slab. In the upper floor, our tiler installed it within the sloped screed.

WilderSueden schrieb:

It looks more like an intermediate ceiling than a concrete slab to me.

That’s what I assumed, since the first post also mentioned a prefabricated hollow-core slab.

Where should the problem be if you can see the reinforcement and it is intact? At the moment, no one knows whether this was planned that way, meaning whether the mesh was cut and installed accordingly, or if the concrete contractor did it on their own initiative.
Basically, making an opening in the reinforced concrete slab is possible; otherwise, there would be no stairs...