Is an 11.5-inch interior wall with opposite switches permissible?

Hello everyone,

in our new building, the electrical work is currently being done. I have noticed that the electrician has installed four switches in the bedroom on an 11.5 cm interior wall exactly opposite four switches in the bathroom. In some cases, even deep wall boxes (approx. 6 cm) are used so that the backs of the plastic boxes face each other without any masonry between them. I am now concerned about sound insulation. The electrician has not finished his work yet, and I could ask him to make changes. In the first conversation, the electrician downplayed the problem, as of course he does not want extra work. Are my concerns justified, and is he required to fix this at his own expense?

It is certainly permissible, if you still have concerns, then just shift either the bedroom or the bathroom by a few centimeters.

11.5 cm wall unfortunately has almost zero sound insulation even without holes. So you can also leave it out, structurally these walls are also uninteresting.

Separating bedroom and bathroom with such a wall is a planning mistake for me.

Is fine. As already mentioned here, 11.5 cm walls are like cardboard. There is practically no soundproofing. I hope you don't get up at very different times..

I also have an 11.5 cm wall between the bedroom and bathroom and I get up much later. I hear nothing. The shower is also along the long side on the bedroom wall. I haven't found that disturbing so far. Maybe also because the water pipes are not in the wall but in the pre-wall installation of the washbasin. Without the pre-wall installation, they probably would have embedded it.

I also have an 11.5 cm wall between the bedroom and bathroom and I get up much later. I don't hear anything. The shower is also installed with its long side against the bedroom wall. So far, I have not found that disturbing. Maybe also because the water pipes are not inside the wall, but in the pre-wall installation of the washbasin. Without the pre-wall installation, they would probably have done it flush-mounted.

Sand-lime brick or maybe just soundproof. Technically, everything goes through there, such walls are actually built as 17.5 cm thick.