Floor plan for narrow semi-detached house - Basement + 2 Good luck + Attic without knee wall

Because of the building envelope and such:

often it is allowed to exceed it for subordinate components like stairs (for the exterior stairs this is probably already the case, right?!) but also for conservatories and bay windows. So you could extend your dining room with a bay window, but then the window above the plan in the basement office would be omitted.

Okaaay... that would be seriously cool. I'll take it with me to the architect! Thanks for the tip!

You are otherwise one knee surgery away from cursing the missing toilet on the couch sleeping floor. :D

And another idea for your dark stairwell: from the well-known skylight manufacturer with "V" there is a "daylight spot," a kind of light tunnel, with which you could bring light into the stairwell.

Possibly also a large skylight from the bathroom on the upper floor towards the stairs and hallway.

And another idea for your dark stairwell: from the well-known roof window manufacturer with "V" there is a "daylight spot," a kind of light tunnel, with which you could bring light into the stairwell.

Possibly also a large skylight from the bathroom on the upper floor towards the stairs and hallway.

Nice idea – I didn’t know that yet! But I don’t even know if we need it that way. That is more for when you have an attic, right? In our case (according to the current plan) the entire space up to the roof will be built out. Actually, I wanted to plan a window above the stairs. But I was advised against it because then it would be roughly 5 - 6 meters above the stairs and therefore difficult to clean, if not only possible under life-threatening conditions.
In the bathroom, I only want a roof window because the photovoltaic system is supposed to go there. The window should then basically replace one – maximum two modules (of course depending on the size of the modules).
Currently, I am planning it like this: a skylight into the bathroom (as you described) and then a frosted glass door into the bathroom. It won’t be exactly 1000 lumens bright, but at least you can go up the stairs without light..

Some input from 18 years of living in a sliced villa:

[*]Light - In the stairwell, proper lighting is sufficient; there the light is functional. In the living spaces, light is part of the quality of life. Think of the dark season and have more window area on the sides – even if it’s just additional light strips. Consider shading for the summer.
[*]Life practice with children - Happy children run in and out playing, running in and out, and from experience, they don’t pay the most careful attention to the things they carry back and forth. Matter in the wrong place means dirt. Top reasons for "in and out" are: "I want to tell you something / ask you something," "I want to drink / eat something," "I have to go." From this comes the practical consideration that the supervisor, toilet, and kitchen should be placed so that the uncontrollable transfer of matter is limited to as small an area in the house as possible. Therefore: toilet on the ground floor (You probably have a great wife, you should listen to her... ;))
[*]Retreat space - visually, we liked the open stairwell that led to the dining area. Along with that came the fact that noises from the table and the living room spread strongly throughout the house, and the need for retreat turned out to be a greater limitation for three of the four to five residents (I didn’t care, guests and exchange students just have to take what they get). In the end, we preferred the staircase to be closed off from the hallway.
[*]Living in the garden - Don’t limit yourself to having exactly one terrace to sit on. Depending on the location of the house, a place to settle in front of the house is a blessing for playing children, supervising parents, chatting with people without having to invite them in, and interaction with neighbors is quite a blessing. A place for sociable gatherings with and without refreshments / barbecue is great. For this place, practical proximity to food logistics and privacy count. But this place does not necessarily have to be the one where you lie in the sun and read a book. Separating the functions of outdoor areas (as you do in the house) gives freedom for outdoor design and makes the topic of "terrace" easier to think about and solve.
[*]Life practice with teenagers - How glad we were to have our own bathroom and our own floor under the roof! I like that.

I find the variant without a guest toilet quite doable. I think going down the stairs to the basement is absolutely reasonable, and by having more space and the possibility of a shower, you actually create real added value in the basement. Always arguing with the broken knee is, in my opinion, pointless; then you have more problems than just the toilet. You can also go directly from the garden to the basement; you can definitely get the kids used to that as well. I would plan the door from the hallway to the kitchen as a sliding door. It will mostly be open, but you can also close it when you want peace upstairs or downstairs. Overall, I like the plan given the external circumstances.