Bathroom renovation: Which cladding to use for pre-wall elements?

Hello everyone,
we are currently renovating our house due to a tenant change.
The bathroom is being completely rebuilt, and a pre-wall element is to be used for both the washbasin and the toilet.
Now I am wondering which boards I should use for the cladding?
Also for the cladding of the shower and the bathtub.
They should not be too bulky, but stable enough to be tiled afterward.
The costs should also stay within reasonable limits.
Which boards would you choose?
Green drywall, Fermacell, or these light and coated construction boards (I might favor these).

Regards, Olli

Isn't there the regulation of the green plates, and then also double?

Isn't there a regulation for the green boards, and then doubled as well?

Hi, no idea, the "old" walls consist of double green drywall boards, with tiles on top. The new tiles are supposed to be glued onto the old tiles on the walls. For the pre-wall elements and the side base extensions, the tiler recommended 18 mm OSB boards and a green drywall board on top. He doesn't think much of the construction boards... What are your experiences? Regards, Olli

We had WEDI panels in our old building, I assume those are the ones you mean, in a sauna anteroom with sanitary facilities. Some were plastered and some were covered with mosaic. They withstood three children and about 10 years without damage. I don’t know for longer because we sold the property then. In our case, it was the low material thickness and modest weight that made them suitable for use. I have no complaints about the material. At that time, many heated loungers were built with it in the wellness industry. There is an electric heater underneath and mosaic on top. However, they were glued and grouted with high-strength swimming pool mortar. I am not aware of any case where these loungers were not stable enough. Best regards Gabriele

No idea, the "old" walls consist of double green drywall panels, tiles are on top of them.

So according to the regulations: green for damp rooms, double for tiles or loads acting on the wall.

According to the definition, a bathroom is not a wet room