Not really sure what you call it but we have this box in our smallest bedroom which is for the headroom of the stairs IYKWIF..
This is a picture stolen off Zoopla of another house in the street who have gotten rid of the box and are just left with the slope - its such a weird and difficult thing to work with!
Any suggestions? I'm assured that a lot of 1930's/early semi's have these but I wonder how everyone else makes better use of it.
Before
after