Floor plan of a single-family house just before final design - Please provide tips and advice

All connections will be installed and the door to the second dwelling unit is also present. Our developer said that this is sufficient.

That should be enough. There are less reputable granny flats. It's fine.

Even though this is the north side, you have absolutely no access from the living areas.

I agree. The good thing is that you get plenty of light into the living rooms thanks to the orientation of the living area.

The main access to the garden will probably be the kitchen.

However, the kitchen also faces north. I would plan the large terrace door to the north for the view into the garden and arrange the kitchen differently: roughly upper cabinets on the right side of the plan, the door to the garden to the north, then window plus kitchen unit on the left side of the plan. Island, possibly for seating, somewhere in the middle. Completely remove the built-in cupboard on the left side of the plan instead of the pantry. The swap of window/terrace could be requested in a change application. It doesn't cost much and can be submitted later. Regarding the wardrobe: if one parent should get the granny flat, you would be without a wardrobe. I would pinch 20 cm from the living room for the hallway so that a cupboard would still fit there. Swap the shower/WC in the upstairs bathroom and get rid of the bedroom windows in the west; they are superfluous and unpleasant (heat and chi).

However, the kitchen also faces north.
I would plan the large patio door to the north for the view of the garden and arrange the kitchen differently: roughly upper cabinets on the right side of the plan, the door to the garden on the north side, then windows plus kitchen units on the left side of the plan. Island, possibly for sitting, somehow in the middle. Completely remove the built-in cupboard on the left side of the plan instead of the pantry.

That is an interesting idea and could make the kitchen layout more sensible. Would a sliding door be worthwhile then, or is a simple patio door sufficient?

Bedroom window in the west gone, they are superfluous and unpleasant (heat and chi)

Thank you ypg. That is the only point where my husband and I agree that we should leave it out :)

The story height from ground floor to first floor in the shell construction is 2.75m. How do I best measure the stairwell? On the first floor plan?

Are the 2.75m really the story height or the clear room height? The interesting measurement is from the top edge of the finished floor on the ground floor to the top edge of the finished floor on the first floor.

Yes, how large is the opening on the first floor plan

Is the 2.75m really the story height or the clear room height? The interesting measurement is from the top edge of the finished floor on the ground floor to the top edge of the finished floor on the upper floor.

Yes, how big is the upper floor opening according to the plan

We should have about 2.60m, but I don't know if the parquet is already included.

The opening on the upper floor is 3.5m by 1m.

A clear room height of 260 cm cannot be achieved with a floor-to-floor height of 275 cm. In each case, the entire floor construction and ceiling thickness must be added to the clear room height. So usually at least 25 to 30 cm must be added to the desired clear room height. The staircase must then be able to overcome the floor-to-floor height.