ᐅ Conduit Costs – Network, Satellite, Backup

And neatly cut horizontally. In the concrete ceilings, I only installed empty conduits for fire alarm and LAN cables; otherwise, I used only concrete cables. But not such a tangled mess all at once...

Sebastian79 schrieb:
And nicely slit horizontally

This is a 24mm (1 inch) wall, so I’m allowed to cut horizontally or diagonally up to 25mm (1 inch) deep over an unlimited length!
The 11mm (0.4 inch) wall on the left in the picture is uncut.

I am not concerned about the structural feasibility, but rather that such a thing could simply be "dangerous" later on.

Why is that considered "dangerous"?

Because horizontal slots are not normally made and no one expects anything there, it is easy to accidentally drill into them.

Sebastian79 schrieb:
Because horizontal openings are usually not made

That is not correct.

Sebastian79 schrieb:
and nobody expects anything there

Everyone should assume something here, since this area is designated as an installation zone according to DIN 18015.

Sebastian79 schrieb:
so you can quickly drill into it.

If a tradesperson drills into it, they are responsible for the damage, because drilling inside installation zones is not done without prior inspection!
And if the homeowner does not know where the pipes or cables are located, they should avoid drilling in the installation zones as well.