Poor floor plan with sloping roof attic

Hello,

we are planning a bedroom and a bathroom in our attic.
Regarding space, there are not many options in the bathroom in our opinion, so we can now place a row of sink, heater, and bathtub; however, the toilet is relatively narrow in width, which hopefully won't bother us.
One box row is 10cm each, the dimensions are rounded up/down to 5cm.

Thank you for your feedback

When expanding, every centimeter counts. 60 cm for the WC is too little. Measure and draw precisely or write down the exact measurements. A 2 m height line is important. Roof pitch? Do you definitely want a bathtub?

Draw the window in. Include dimensions and sill height.

The toilet is relatively narrow in width, but hopefully that wouldn't bother us.

Well, you do need some room to move on the toilet, even if you gain 10 kilos. But even slim people need to be able to move their arm. To me, based on the height dimensions, it looks more like a cramped space. There’s no window either, right? Maybe consider installing sliding doors in front of the slant instead of a sliding door wardrobe and using it as a closet, and in the closet space arrange something like a bathroom (whatever kind of room that is).

There is a contour line at 180 cm. To the left of it, how far down does it go? In that area, do the pipes come up from below? How should the WC drain pipe run?

I rather see storage space to the left under the assumed sloping roof, and the wall on the right might still be adjustable.

A complete floor plan of the level would be helpful.

There is a contour line at 180 cm. To the left of it, how far down does it go?

I thought I read 30 cm.

I also think by now that it will be too tight with the toilet, so it’s better to install a built-in cabinet there and forego the bathtub in favor of a shower. We already have a bathtub on the 1st floor. Then the sink, radiator, toilet, and shower can be arranged differently.

I have already asked in another thread about how to manage the drainage pipes, especially from the toilet to the downpipe in the basement. This is a mystery to me because of the slope of at least 1cm and the thickness of the pipes.

Attached is the total area of the attic. The wall marked in red was not built at that time.

The currently small roof window would be removed and replaced with one of the same size as on the other side.