What is this part of my house?!

[sanpelle]

I posted about this a while back but no one seemed to know any answer to my questions. I'm so confused! I'm living in a mid terrace private rent with a 3rd level bedroom that has half of the room cut off. So it doesn't extend to the full length of the house. There is a thin hollow wall blocking the rest of the 3rd level. I've never experienced anything like it. All the neighbours have bedrooms that extend to the length of the house (seen in rental listings pics).

There is no access to it anywhere for me and I'm just bemused at why anyone would have a large section of their house blocked off so they can't maintain it. I could hear workmen behind the wall when my neighbours had their roof done and I'm not sure why they would be in my house. I've never heard anything else. Do my neighbours own part of my house? I just don't understand and my LL isn't easy to contact.

If anyone needed to access that area from inside my house then the walls would have to be knocked through. It just doesn't seem practical if there's pipes or such behind there that might need maintaining. Might be the reason behind all the damp in the house though! Maybe it's just a room full of pipes and mould, my LL has been known to cut a few corners. There's no insulation in the house at all so can't be that! I'm so puzzled

We used I live near a row of terraces from on old mill company.

The rooms in them crossed between the house as when the mill owned the houses if one worker needed an extra room they’d knock through.

Could be that at some point that area was sold to a neighbour.

I think the conclusion that my neighbours own that part is probably the most likely now! There's no skylight window on it but there is on their house so they probably use it for storage as some PPs have said. They've got to have a door to it for the workmen to get into as I doubt they would have come through my roof would they?

Have you not asked them??????