Ground floor approx. 100 sqm, upper floor expandable (planned bathroom, 2 children's rooms, 1 storage room)

I find it pretty idiotic to make a hallway on both sides right away. That way you lose even more space. Here is again my last draft with furnishings and a wider hallway. That one child is now in the north and the other in the south, I don't find that too dramatic in this case. More important is to use the space sensibly. I would rather add skylight windows later. The staircase is rotated with a 1/4 turn at the start.





I would also redraw Yvonne's suggestion neatly, but I really can't make out the gibberish.

We have laid out the possible floor plan using roof battens.

That is a good idea. I suggest refining it by also placing (possibly differently colored) roof battens where the plumb line of the 2m line meets.

I have tried to draw it in.

And thereby, in any case, at least an excellent illustration is created for even the last nonbeliever that with a pitched roof without knee wall it is a perfect blunder to place a straight staircase under the ridge: you can hardly stand in front of it after the staircase landing hallway, room wall, and closet behind it, even if it has sliding doors.

1. Does the shower fit like that?

If it is only about fitting and it does not have to look nice, yes.

2. Is 8 cm insulation in a 14.5 cm wall enough? The roof is not insulated until the conversion.

You mean because of the air gap? – there should be no problem between rooms that are equally warm on both sides.

4. The statement was that he did not know that underfloor heating (gas) with dry screed works on a wooden beam floor. [...] Is there a difference between gas/geothermal?

The warm water in the heating system should not care what the boiler burns. Maybe you use classic radiators upstairs?

I find it pretty idiotic to make a hallway on both sides right away. That way you lose even more space. Here again is my latest draft with furnishings and a wider hallway. That one child is now in the north and the other in the south, I don't find that too dramatic in this case. More important is to use the space sensibly. I’d rather add roof windows later. The stair is rotated with a quarter turn at the start.





I would actually redraw Yvonne's suggestion properly, but I really can't understand that gibberish.

Ok, I'll do it again.
By the way, yours doesn’t work because the windows are closer together.

By the way, yours doesn't work because the windows are closer together.

Weren't they at the 2m mark? Where exactly doesn't it work?

Weren't they at the 2m limit? Where exactly does it not work?

Your 2MeterLine is wrong

So, I've done it. . Including all transferred measurements that are known. Exception: I have used the values from the OP for the centerline, since everything seems to be shifted by 5 cm on his side.



For me, the bathroom doesn't work

But now... based on Katja's designs... Although without looking, the hallway has turned out the way I remember Katja's designs With the dimensions of the TE