Building expert or lawyer? Who can help us?

So if I read that correctly, there should be a parapet height of 27 cm (above the raw ceiling) or 12 cm above the floor for a double window or a double door with a height of 2 m (+25 cm for the roller shutter box) over a width of 1.51 m. And that twice.

yes, that is correct and now you have a passage height of about 170 cm due to the window frame so that I, being 185 cm tall, always have to watch out there and also have the 50 cm wide obstacle (step) in the floor area the 2 obstacles 170 cm passage height and 50 cm wide step are really quite unusual and even pose a danger... so for me, this has nothing to do with a balcony door but it is simply a large window and in my opinion a "planning error"

But you have approved the factory planning exactly like that,

You approved the workshop planning exactly like that,

I agree, you get what you ordered.

Hello,

Thank you for the plans!

we have a problem with our balcony exit
the developer says everything was installed according to regulations (and construction plan)

However, the access to the balcony did not become a door (as one would have thought based on the construction plans)
but only a large window, with a passage height of about 170 cm
and a windowsill inside/outside totaling over 50 cm obstacle to overcome.

Since we are laymen, we cannot argue technically enough with the developer.

What should we do in such a case?
go to a lawyer?
hire a building expert?
or???

If you approved the submitted construction plan as is, you can (almost) do nothing. That means you can save yourself money for a lawyer or expert (a bit late) in a dispute with your developer, because the parapet window to the balcony is installed exactly as built (at least according to the pictures in the green forum; I got the link from another user), just as you approved in the drawing.

“Almost” because you can have the window replaced at extra cost, which will not be insignificant. Because, unlike how the responding users in the green forum apparently see it, access to a cantilevered balcony is possible even with a parapet height of zero from the adjacent living space, as you can see in the attachment.

Rhenish greetings

hm, I do see the point about "approved by the client" but shouldn’t the unskilled client also recognize such a (in my opinion absolutely unusual) hurdle? Especially since it is obviously also marked as a 'proper' balcony exit, not just as a French balcony) - isn’t there something about a surprising clause? Oh no, that was hidden in the [AGB]...

Just thinking out loud, maybe it helps with the argument?! Good luck!