130 m² bungalow with double carport on a 600 m² plot?

It is also not a spiral staircase.

Thank you. Let's see what the next draft brings. There are definitely optimization possibilities for us. Size-wise, we are already quite stretched in terms of the property... But it will work out... We are still optimistic about that. You can't get a couch up the stairs, can you? Since we will use the attic as storage, I want to have relatively easy access up there. The architect will have to figure that out somehow.

At our place? Of course you can get a couch up there. Why not! That's a completely normal apartment staircase. Now, consider when you look at our plan that it's only 108 sqm. You want 130. So you could definitely make it bigger. For example, we don't have a bathtub so that our relatively small bathroom appears large. And it does. The living room could be a bit bigger, because of 570 sqm of land and a floor area ratio of 0.25, but due to the terrace, that was all we could do. There's always something. Our bedroom is definitely big enough. We just arranged the furniture differently than in the drawing. The kitchen and utility room are really okay. The hallway too. The two small rooms, guest and office, if built as children's rooms, should be around 14-15 sqm. Karsten

Nordlys has a completely normal 2-quartered staircase, as is commonly installed in terraced and semi-detached houses. Many of the single-family house builders in this forum have also chosen this staircase variant because it wastes the least amount of space.

There is also the option of a straight staircase with step-wise storage underneath. Maybe I just have to say goodbye to the long straight staircase... Are they available a bit wider - more spacious? Somehow it doesn't look very practical to me. But maybe you just have to go to a staircase specialty store... Like an exhibition where they also have staircases... If you want to lug a home trainer up there, you probably have to twist around quite a bit...

Do you think one can build on the floor plan? I mean in terms of the dimensions? Or does it have to be completely discarded?

The floor plan is not that bad, but as a principle I would develop alternatives not as variants but as independent concepts.

since part of the attic will become storage space and the other facing south a kind of studio for the junior

Or junior downstairs and study upstairs?

If you want to carry a home trainer upstairs you surely have to rotate quite a bit..

Then you just have to do a bit of home training beforehand.