Floor plan house with granny flat - improvement suggestions?

I fear this proposal confuses more than it helps. It neither meets the requirements nor can it be furnished, and regarding the approval of the terraces, things look bleak in my opinion. But basically, it would be worth considering whether a 2-family house is an option in any form, also with regard to future use.

Well, it is just the question whether it makes sense to plan an almost unsellable house. And the floor plan can definitely be furnished (just roughly sketched by hand). And the terrace can also be significantly reduced. There is no other way with this plot.

Well, the question is whether it makes sense to plan a house that is almost unsellable. And the floor plan can already be furnished (just roughly sketched by hand now). And the terrace can also be significantly reduced. There is no other way with this plot.

Furnish again with the promised 3rd children's room where the kitchen is on the ground floor. Everything else is irrelevant. But I agree with you that the original poster is planning a house that will be hard to sell. When all the children have moved out (which is foreseeable), it will be a monster that can hardly be rented out either. The entire upper floor will then be practically a ghost house. I wouldn’t find it so dramatic for young people to walk down from the first floor to use a barbecue area or something similar there.

I think dividing it into a two-family house shows that the space requirements of the living units are completely different. The children's rooms downstairs are too small to be used by two, there is no wardrobe, there is no storage room. If you draw the furniture to scale, it will be partly tight.

Well usable living units must be designed that can be rented out if necessary. Otherwise, it will really become a ghost house. If push comes to shove, in 15 years only 2 people will be living in a house that was once planned for 8.

If the building application is submitted today, when would the move-in be? Sometime at the end of next year. What about the 17-year-old today? Will he stay here or leave for training and only come sporadically? What about the brother? Is it foreseeable that he will look for an apartment or does he want to stay in [Hotel Mama]? I don’t want to throw anyone out, but these two people are the shaky candidates that we are worrying about now and who then hardly move in. Maybe one room shared by both is enough for them.

Yes, with the 3rd children's room it will become tight downstairs, the kitchen would have to be relatively small like on the 1st floor. What she says is the only right thing. You have to think about how many people will actually live in it. Otherwise, by the end of the construction period you might have a house that no longer meets the needs.

I think the division as a two-family house does show that the space requirement of the residential units is totally different.

The targeted division 2:1 certainly does not fit into a classic two-family house, but in my opinion, it is realized relatively most favorably here with the larger unit as a maisonette and the subordinate apartment dominant on the ground floor.

What about the 17-year-old today? Will he stay here or leave for training and only come sporadically?

Well, I guess we probably have to guess three times if the uncle is setting a bad example as the eternal student ...