Fault arc circuit breaker in prefab house

The keyword in my question was "blondinenverständlich" - well, I guess I'm no wiser than before :-(

I already explained it briefly further up.

If my installer came with that, he might as well pack up his things again.

So by now we have talked with Keitel-Haus and after research they informed me that I am right and they do not have to install arc fault circuit interrupters for me.

That makes me happy...

Proofs are always useful.

So by now we have spoken with Keitel-Haus and after research they informed me that I am right and they do not have to install fault current protection switches for me.

That makes me happy...

With what argument / proof did you convince them now?

Hello again,

Keitel-Haus was very approachable. I don't think it is in their interest to have those things installed, because that tends to make timber construction less attractive.

I was informed that we can do without the switches.

Best regards,
Florian