Renew plastic water pipes?

Hello everyone,

I have the following problem and would like to hear some expert opinions on it. I am currently renovating my condominium (built in 1986). In the bathroom, which is currently in the shell stage, all the water pipes (plastic) are exposed. So it is no problem to renew the pipes there. However, there is also a guest WC with a shower. The water pipes there run under the screed from the bathroom to the guest WC. According to the installer, the pipes do not need to be renewed. But I am now unsure about that, as I actually want to have peace of mind for 20 to 30 years after this renovation.

Should the water pipes be renewed? If yes, is it sufficient to remove and replace only the screed at the location of the pipes, or should the entire screed be renewed?

Hi, why do you absolutely want to renew the cables? Are they somehow damaged? Regards Olli

According to the installer, the pipes do not need to be renewed.

I would agree with Grundstück without knowing the exact condition of the pipes.

If yes, it is sufficient to remove and replace the screed only at the location of the pipes

Yes, that would be sufficient.