Floor plan design single-family house on south-facing slope

Is a gable considered a roof structure according to building regulations?

Katja's design is a cross-gable. There is - as is often the case - no legal definition in building regulations for the term. However, case law assumes that cross-gables are not roof structures. Therefore, I do not see section 1.3 of the local building regulations as applicable. These also do not exclude cross gables. While the roof pitch appears to be within the permitted range, the eaves height is probably exceeded. The approval capability is therefore doubtful and should at least be discussed with the approval authority.

Regarding the driveway situation, I see no alternative and actually don't find the planned solution bad at all. The neighbors won’t be gawking up at you much from their convertibles anyway. Maybe something with rotating slats can be added to the railing; wind won’t be less of an issue there than views (without obstructing the views).

The orange area... you stand on the stairs there and bump into the bathroom floor.

Ouch. Unfortunately, I see it the same way. Nice that the criticism of the planner is coming from the OP this time instead of me

I would put the child downstairs; upon moving in they’re 18 years old, ...!

With "their own space," however, it will last even longer

One can also tell the architect 'redo it, I don’t like it.'

An architect owes a permit-approvable design. The consideration for their fee is provided independently of whether the builders find the design beautiful. Even less so is the architect obliged to optimize based on Katja’s design.

whether one may even build a gable in that form due to the attached excerpt from the development plan, since "roof structures" must have a minimum distance of 1.5 m from the lower roof edge.

This development plan clearly does not refer to a dormer (= a "Gaube" when it rests on the house wall instead of the knee wall — which you avoid by the knee stock). I see it as possible there but not to be called a "structure." From my point of view, it is a part of the roof with an auxiliary ridge.

Regarding the driveway situation, I see no alternative,

P.S.: I had forgotten this earlier – I consider the support pillar in the garage beneath the corner of the house to be necessary or at least not really disturbing there and only replaceable with disproportionate effort.

One more to go.

Child in the basement – at 18 years old I wanted that too. Garage northeast – level with the front door – little sealed area for paths. No cars in the house means peace.
Terrace deliberately aligned towards the cozy garden and not, as usual, on the display platter. Parent's bedroom with south-facing balcony.

- Whirlpool – check
- Fireplace – check
- Laundry chute – important bonus
- Pantry – check
- Sauna – check
- Fireplace in the living room possible – check – (not yet drawn)

well done........ I would personally prefer if there was only one door to the living area, the door exactly opposite the stairs and both doors removed?

Is TV being watched?

personally prefer it if there was only one door to the living area, the door exactly opposite the stairs and both doors gone?

Is the TV being watched?

At the moment it doesn't matter at all. These are examples of how one could build... nothing here is set in stone, nor do small details need to be discussed.

An architect owes a permit-approvable design. The consideration for his fee is therefore independent of whether the clients also find the design beautiful

What world are you living in today?
An architect billing according to HOAI owes me more than just a permit-approvable design, but also one that pleases me.
According to your statement, an architect could just draw a flair and add the invoice. No no... lol
I hope you'll be well rested again tomorrow.