Ground plan design single-family house 165 sqm without basement on 400 sqm plot

Yes, I would prefer the first layout. Do you have approximate sizes for the living area and, for example, the utility room and WC?

You can copy the images and then scale them until you have the 12 cm length. Then you can measure it out.

I have now put together the following. This time with the realistic wall thicknesses and dimensions. I have adapted the hanghaus idea a bit to my wife's wishes. Kitchen and carpenter-built-in wardrobe for the cloakroom. This is how we could imagine it well. I have only roughly placed the windows for now. Under the stairs, there would now be a mini storage/pantry. At least it looks quite tidy. We are still with a 12x9.15 m building volume.

Measured out quickly here.

Here quickly measured out.

Very good. I have similar measurements in my amateur sketch as well.

Your planner has planned 40 cm exterior walls. In my opinion, timber studs are also possible with 30 cm.

You have reduced the width of the house to 8.8 m?

The installation wall for the WC is not required to that extent. A facing panel for the WC and sink is sufficient.