Is the wall load-bearing?

[SBH]

Yep, a regular floor level (residential apartments) above me, plus the attic.

I'll try to figure out how the floor joists run tomorrow!

But as I wrote earlier, there is another wall in the apartment that runs parallel to the wall I want to tear down (but perpendicular to the rafters) which is considerably thicker and likely solid concrete. It glimpses in the background of the photo I posted earlier, it's the one out in the hallway.

oh you have that variant.
are the walls to the left and right concrete or wood?

 

[coldmejl]

I'll go ahead and knock down the plaster all the way from ceiling to floor tomorrow and check what the planks are attached to. I'll upload some more photos then as well.

 

[coldmejl]

oh, you have that variant.
Are the walls to the left and right concrete or wood?

Both left and right are concrete.

 

[SBH]

Both right and left are concrete.

then you have a very high chance that your wall is not load-bearing.
you should think like this. where is the greatest strength concrete or wood?

 

[Odjuret]

Keep in mind that you need permission if you are going to tear down walls...