Single-family house 130-140 m² floor plan planning

The additional floor-to-ceiling window on the ground floor then reduces the available space there. We wanted to place a sideboard next to it. The window with a sill was planned because the couch is going there. Then a floor-to-ceiling window doesn’t bring me much if the couch is in front of it.

I thought the same, why a floor-to-ceiling window if you only see the back of the couch and can’t look outside anyway?
First, you can pull the couch a few centimeters away, it doesn’t have to be flush against the window, and second, a floor-to-ceiling window has a significantly greater effect. As already mentioned, preferably also wider, so maybe even wider than the couch?

With the window in the dressing room... when I think about the fact that I change there most of the year when it is dark anyway. So why have a window at all?

Is that so?
Maybe you are still saving on controlled residential ventilation, then you could ventilate?!
And surely there will be situations with you (wardrobe being stocked, cleaning), when one wants daylight.
Besides, a chair also quite likes to be placed under a window.

Is that so? Maybe you are still saving on the controlled residential ventilation, then you could ventilate?! And there may certainly be situations with you (wardrobe is being put away, cleaning is being done), where you want daylight. Also, a chair would quite like to be placed under a window

I would never make a room without a window, no matter which one (we also gave our storage room a window, and that was a very good decision). And I think it is easily possible in terms of space.

I would also give Child 2 a second window on the northeast side; Child 1 also has light from two sides, which simply makes the living feeling nicer.

I would also implement Katja's proposal for the bathroom layout as is. I would only either move the window in the shower to the right side of the plan (outside the direct water spray) or make a wide light strip at the top.

Front almost ok - but why aren't the gaps perfectly symmetrical?

Symmetrical, she said symmetrical.

I would never make a room without windows, no matter which (we also gave our storage room a window, and that was a very good decision).

I completely agree with you, I would rather do without furniture, square meters, etc. than without windows.