Make an in-wall cable duct yourself?

if you plan to do such a mess (15 cm thick exterior wall to the neighbor, chipping 6 cm deep) then I would have the construction company provide written confirmation of compliance with soundproofing. You don't want your neighbor to sue you or for you to get totally annoyed by him, his children, and the sound system...

@Pacmansh do you know the dimensions of the flush-mounted duct and how thick the wall to the neighbors is?

what solution do you have? Also such an embedded cable duct?

Maybe just buy something very flat and simply put it into the wall? I can't imagine that such a cable duct is statically relevant in practice.

Unfortunately not. But I think it is just an empty conduit, and he said it was quite annoying to get the plug through. So the diameter can't be very large. I believe the walls were probably double-layered, 2x15.

What would you recommend?

my wife would like to have a lowboard underneath to be able to put decorations or other things on it.