Sanitary facilities and noise

Thank you for the answers.

Can someone explain to me exactly how the water pipes are decoupled? I know that they are insulated, but the pipes have to be secured somewhere, right?

By using, for example, fastening clamps with rubber inserts or [GIS Rohrclip] for supply lines. But even the use of [Silent-db20] pipes makes a big difference compared to the classic HT pipe.

By using, for example, fastening clamps with rubber inserts or GIS pipe clips for supply lines.

But even the use of Silent-db20 pipes makes a big difference compared to the classical HT pipe.

Thank you, Kaspar, do only the water pipes need to be decoupled, or also the sewage pipes?

Both. In particular, for wastewater the plumber can sometimes use soundproofed [directly]

And does this only apply in the bathroom or do the pipes throughout the entire house need to be insulated? How much would that approximately cost extra? I also have a second question: Are these pipes insulated during the rough plumbing phase or the final installation? Background: We want to exclude the final sanitary installation from the contract with the heating and plumbing company, as it will be done by relatives (who also work professionally in plumbing and heating) since we will be providing the equipment ourselves.

Another question: What do you think of the bathroom fixtures? I can still change quite a lot, just not the dimensions of the room.