Wall thickness children’s room / bathroom

Good evening,

has anyone by any chance had experience with how the wall thickness affects sound transmission?

Currently, the shower is planned directly on the wall to the children's room. In the children's room, a cupboard is planned on the wall to the bathroom (a desk is still drawn here, the children's room window will be moved so that the cupboard fits against the wall). Currently, a 17.5 cm thick masonry wall is planned. If a 10 cm masonry wall would be sufficient without being audible in the children's room, we could allocate these 7.5 cm to benefit the shower. Are there any experiences?

Looks more like an 11.5 cm wall – or what thickness should the interior walls to the hallway have?

More important than the thickness should be the information about what kind of stone you have.

They are perforated bricks. I don't know the exact measurement to the millimeter. I only remembered approximately 20 cm and approximately 10 cm.

We built with Ytong and in my opinion, the wall thickness of 17.5 cm is a must for the bathroom.
We also have a wardrobe spanning the entire width of the said wall.

In hindsight, we should have built a 17.5 cm or preferably even a 24 cm wall between the teenage room and the bedroom.
Skype chatter or curses during online gaming in the middle of the night initially led to various discussions for us.
We hadn’t noticed it until we moved into the new house because our kids had their own floor.

The best wall construction is usually useless because the doors are no good - very few people pay attention to that.

Ytong is actually really bad as an interior masonry because of sound insulation.

We have a 23 cm aerated concrete wall between the bedroom and bathroom - but mostly because of the built-in mirrored cabinet.

Reasonable doors cost money, and that's usually where savings are made.