ᐅ Bathroom Renovation: Which Cladding to Use for Pre-Wall Installation Elements?

Hello everyone,
we are currently renovating our house due to a tenant change.
The bathroom is being completely rebuilt, and for the sink and toilet, we want to install pre-wall systems.
Now I’m wondering which boards I should use for the cladding,
also for cladding the shower and bathtub areas.
They shouldn’t add too much thickness but need to be sturdy enough to be tiled afterward.
The costs should also be reasonable.
Which boards would you choose?
Green drywall panels, Fermacell, or these lightweight, coated construction boards (I might favor these).

Best regards, Olli

Isn't there a regulation requiring green boards, possibly even double layers?

ypg schrieb:

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

Hello,
no idea. The "old" walls are made of double layers of green drywall panels, with tiles on top.
For the new walls, the idea is to glue the new tiles directly onto the old tiles.
For the pre-wall installation units and the side base extensions, the tiler recommended 18mm (0.7 inch) OSB boards with a green drywall panel on top.
He’s not very fond of the construction boards...
What are your experiences with this?
Best regards, Olli

In our older building, we used WEDI boards—I assume that’s what you mean—in a sauna anteroom with sanitary facilities. Some were plastered, others covered with mosaic tiles. They remained undamaged despite use by three children over about 10 years. I don’t know about any longer, as we sold the property then. For us, their low material thickness and light weight were the reasons for choosing them. I have no complaints about the material.

At the time, many heated lounge chairs in wellness facilities were also made with this material. An electric heater is installed underneath, with mosaic tiles on top. However, they were glued and grouted using high-quality swimming pool mortar. I am not aware of any cases where these lounges weren’t stable enough.

Best regards
Gabriele

Olli-Ka schrieb:

No idea, the "old" walls are made of double green plasterboard sheets, with tiles on top.

According to regulations: green boards for wet rooms, double layers for tiles or loads applied to the wall.

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