Floor plan of a single-family house approx. 200 sqm with basement - rear development

Sorry, was a bit under fire, hence the late reply.

The large children's rooms are more a result of the layout being stretched out as mentioned by ypg than a deliberate decision. And since I suspected that a window facing west or east might be a bit dark, I planned the dormer there. I completely agree that 15 sqm is sufficient for the kids. Regarding the lounge: We currently use the living room mainly in the evenings for watching TV, so I placed it in the potentially dark northwest corner. To still have a brighter, cozy seating area, there is the seating lounge, basically a substitute for a conservatory.

The basement would be used for technology, storage, hobbies (sports, aquarium) and, if the project ends due to lack of money, possibly as a small home cinema. I am aware that the basement is a huge cost driver, but I wouldn't currently put it up for discussion. We belong more to the "collectors" faction than the "this doesn't need to be kept anymore" one.

So for 2,500 €/sqm I would expect something more than standard; the house is not supposed to be in Bavaria ;-) But I realize that 600,000 will probably be tight.

Yes, about 25m x 3m is probably what it will be.

If I now approach the hypothetical task to make the floor plan single-story with minimal changes, i.e., put a gable roof on, I see the following problems:

[*]The windows of the children's rooms facing east/west will probably have to be quite small due to the roof pitch as they have to move closer to the ridge -> Dormer with south window as a solution?
[*]Bathroom would likewise only work with a dormer
[*]Apart from that, the kitchen in the original is probably less fussy. Apart from the fact that I would also install a window there to have a view of the garden while cooking, it would probably annoy me by the fifth time digging out the kitchen machine that there is no sensible fixed place for it in the kitchen. But I guess you have to swallow that pill for such a designer kitchen :)

The probable result will be that the floor plan of the Bien-Zenker 172 is not suitable for a gable roof / single-story and I better start from scratch :)

Only something salty would go into the aquarium ;)

For some, the children's rooms are simply larger than the living or dining areas of others. ;) That's fine, as long as the budget allows it. But overall, the floor plan is not coherent (kitchen, bathroom, etc.), as has already been mentioned. You can shift or even reduce a few square meters. Sometimes less is more.

But I have learned that it is called a planning error.