Building window on the corridor map - approval

I didn't quite understand that either. A bay window doesn't change the number of floors, does it? So a two-story building is supposed to become a bungalow because of a bay window?

The bay windows increase the ground floor area in such a way that the main body (rectangle or square in the footprint) on the upper floor falls below 75% of the ground floor area.

Don’t hold me to the exact size now, because the two-story regulation is different in many countries: sometimes it’s 70%, sometimes 75%, or 2/3... my knowledge on this is not set in stone either, and my construction time was also a long time ago...

But the architect should then know the figures according to the building country. That’s what he’s there for, to a) calculate the number of stories, b) plan the house according to the development plan, and c) make use of a small building envelope.

In my example with our "neighbor," the local person from Schwörerhaus told me himself back then that this is a legitimate option.
There’s no need to doubt that now.
Incidentally, a city villa from the advertising brochure is not automatically a two-story house.

In my example with our "neighbor," the local representative from Schwörerhaus himself told me back then that this is a legitimate option. You don't have to doubt that now

That may be true that he told you that, but the advisor's statement is by no means necessarily correct.

That may be true that he told you that, but the advisor's statement is by no means correct.

It depends: some state building codes or development plans allow so-called subordinate structural elements, such as bay windows, outside the building envelope. If that is the case, they still count towards the footprint, thus increasing the scope for a suitable upper floor that should/must not become a full storey.

Basically, I would not say that this is possible either, but it can be worth taking a look, even if it will probably be of little use to the original poster in this case.

Best regards
Dirk Grafe

I understand that a bay window adds more living space. I also understand that the increase in living space then also applies to the attic. What is not clear to me is how this would turn a two-story house into a one-story house. Maybe I need to visualize something like this in drawing form.

Regarding bay windows, pergolas, entrance canopies, garages, etc., I hear different statements. Some say all of this may only be within the building envelope, others believe that these things are allowed to extend beyond it. Maybe it varies from property to property.

I am aware that a bay window adds more living space. I am also aware that I then have the increase in living area in the attic. What is not clear to me is how that would turn a two-story house into a one-story house.

It depends on the maximum ratio of living space between the ground floor and the upper floor. For example, if you have 100 m² on the ground floor and a full floor counts from 75% upwards (according to the respective state building regulations and/or stipulations in the development plan), but the upper floor has 80 m², then the construction is not permitted. If the upper floor remains at a maximum of 74.99 m², then in that case a building permit will be granted.

Misleading is the term full floor, because the upper floor can already be counted as a full floor from, for example, 66% or 75% upwards can or must.

However, if you are close to the limit, you can increase the ground floor area through bay windows so that the upper floor becomes smaller in relation and you might possibly fly under the radar. It is, however, the architects' task to exploit the building envelope in this regard if that is possible or necessary.

Regarding bay windows, pergolas, entrance overhangs, garages, etc., I hear different statements. Some say all of this must only be within the development area, others think these things may protrude beyond it. Perhaps it varies from plot to plot.

That has nothing to do with personal opinion but with the building regulations applicable to the plot. In your case, these are the state building regulations of Rhineland-Palatinate and the specific stipulations in the development plan.

Best regards Dirk Grafe