"Townhouse 'Villa' as a single-story without an extension possible in Lower Saxony?"

Hello everyone, is there a possibility to build a townhouse "villa" without extensions in a single-story construction area (Lower Saxony) (ridge height 9m)? Should the upper floor have a minimum ceiling height of 2.4m? Or can it only be realized on the ground floor with extensions such as bay windows, heated conservatories, etc.? Thank you very much

Is there a possibility to build a townhouse "villa" without extensions in a development area (Lower Saxony) (ridge height 9m) with single-storey construction?

Yes, with a knee wall of about 1.80 to about 2.10 and an appropriate roof pitch

Should the upper floor have a clear height of at least 2.4m?

That contradicts single-storey construction.

Some do it with an open space. However, that costs money and affects the floor plan. The ground floor then has to be larger again, and then one might rather resort to an extension.

I always say: wrong plot, keep looking... or just be flexible.

Is there a possibility to build a townhouse "villa" without extensions in a residential area (Lower Saxony) (ridge height 9m) with single-story construction? [...] or can it only be realized with extensions, i.e. bay windows, heated conservatories, etc. on the ground floor?

By "extensions" you probably mean anything that makes the ground floor larger than the upper floor (?)

The upper floor should have a clear height of at least 2.4m?

Either or neither, braid or bare: if you want a second floor practically against the will of the development plan, then there are only three possibilities, namely
1. make the ground floor as a very full floor so large that the upper floor/attic floor as a relatively less full floor cannot be counted
(that is, let the ground floor extend extensively) or
2. make the upper floor and attic floor equal in size externally, but assign partial areas of the upper floor/attic floor to the ground floor
(that is, provide partial areas on the ground floor with open spaces that then do not count as floor area for the upper floor/attic floor) or
3. actually build less countable area on the upper floor/attic floor
(that is, an upper floor as a recessed story with actually less area or an attic floor with a correspondingly high u230 proportion).

now we would like to build a "cube house" with a flat roof

That was two years ago. Plenty of time meanwhile to present a concrete house concept less academic, what it is supposed to become.

What do you actually want or what is it about: do you find "anything that is not a cuboid block" aesthetically so impure that the question "how many rooms of which sizes for how many people and for which purposes" is miles behind it?
Letting a plot lie fallow for two years (because without such there would be no applicable development plan) just because you have not yet found a loophole for a de facto two-story but de jure single-story house, is already a bit crazy ...

That's a pity, yes unfortunately I am inflexible or wallet and development plan do not fit. We once built a house in Schleswig-Holstein, where it was possible to build a townhouse with the only disadvantage for me that no roller shutters were possible on the upper floor because of the height... we had about 1.80m high windows upstairs and then the roof slope started at 20 degrees. I always thought that it would be possible exactly like that in Lower Saxony, but then with at least 1.80m high windows + roller shutters....

Acquaintances in Lower Saxony have planned the ground floor slightly larger than necessary, the upper floor set back a bit all around, and then a gallery/void space. Well, if you have that much money left over without function, you can do that. To save money, why not build what the development plan allows without expensive tricks?

I always thought that it would be possible exactly like that in Lower Saxony

It is not the state building code, but the development plan that prescribes a one-story house here. The state building codes only differ between three-quarter and two-thirds states.

at least 1.80m high windows + roller shutters

You don’t need roller shutters in the dressing room and bathroom, and while the teenagers consider the roller shutters important (but not the window height). So you can make a dormer with roller shutters on the tall windows in the bedroom and that solves the problem.

Acquaintances in Lower Saxony planned the ground floor somewhat larger than necessary,

From the answer in post #4 I still don’t see what is so bad about the “extensions.”

that’s a shame, yes unfortunately I am inflexible or wallet and development plan don’t fit

If you can afford two years of land financing without use to satisfy your housing needs, there can be no complaints about your wallet.