Floor plan design single-family house with around 150 m²

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I thought so too. Definitely in the guest room. The problem is that I don't want to do it simultaneously in the living room because I don't want a window on that side (because of the neighboring house and the sofa).

Here you write that you don't want a window on the "side" in the living room... then I advise you to go for the window or terrace door, then the window would never bother you.

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What about the window above the sofa? Nobody has complained about that yet. In most houses, you now see windows or even floor-to-ceiling windows behind the sofa (which makes even less sense)..

I never said anything about floor-to-ceiling, did I? And if nobody has complained yet... you only posted the plan 2 hours ago. As far as I'm concerned, yes, it could be removed. But you want it, and to that I say: it could be set back a bit more. Visually, it stands out from the house... I would recess it by 30-50 cm. But that's not a defect if you discuss such things.

What makes an "interesting" facade? Many dormers? If you look at other providers like Viebrockhaus, you mostly don't see anything different there either...

No, no dormers. Arrangements that are designed aesthetically so that it looks pleasing and also makes sense in the floor plan. An architect had design as a subject and should bring a bit more to the table. But I'm out now... I've written my opinion. Done!

What makes an "interesting" facade? Many dormers?

Wrong answer :-( No, you can achieve that quite simply by not clinging to symmetry. It's not about a hundred grams more originality. Often it is enough to simply refrain from getting in your own way with a fixation – whether that's symmetry, or a chimney, or corner windows, or T-baths, or whatever. It's your house. I don't see anything about it that I would feel the need to advise against. None of us discussing here has to move in there.

Here you write that you don’t want a window on the "side" of the living room... then I advise you to go with the window or patio door, then the window will never bother you.

Sorry, I expressed myself completely wrongly there. I definitely want a window on the side, but not so close to the outer wall, so that no one stares at the sofa.

As far as I’m concerned, yes, it could go away. But you want it, and to that I say: it could be recessed a bit more. Visually, it stands out from the house... I would recess it by 30-50 cm. But it’s not a defect if you discuss something like that.

Wouldn’t the living room become totally dark if it were gone? Moving it further in will be difficult since I still need space for the piano next to the sofa. And there shouldn’t be a window there. Originally I first aimed for 50 cm, but the architect intervened there.

I have addressed the problem of the windows on the upper floor and moved the windows in the bedroom and children's room about 20 cm towards the exterior wall. This results in about 75 cm of space between the window and the interior wall in the bedroom for wardrobes. In the children's room, there is not quite as much (40 cm), but it doesn't have to be. Because of this 20 cm, the underlying windows on the ground floor are exactly centered. I have recreated this view, what do you think about it?

The chimney in the bedroom will probably be about 3.25 m away from the exterior wall, so it will be tight to achieve alignment with the built-in wardrobe with these dimensions?

Due to these 20 cm, the underlying windows on the ground floor are exactly centered. I have recreated this view, what do you think about it?

Well, it looks a bit more pleasing.