We are semi detached built in an L shape and at some point our neighbours have extended out into the space.
So it's like have an extra extension from our house but not iyswim. I feel that a diagram is probably necessary and will post one!
We have damp in the room the other side of this extension so water is entering the gap between the two houses.
We don't have a damp proof course as v old house. They would do on this modern extension so damp wouldn't effect them. So water comes into the gap, and out into our room.
Builder suggested the water is entering the gap because their lead flashing has failed. This would not be helped by the fact we are concrete rendered but whose responsibility is the lead flashing? Theirs because it's on their extension- or ours because it's causing us the problem?
They also had an attached lean-to against our wall which they have knocked down. This had a gutter across it that took the rainwater from both our extension and their lean-to, to their drain. Now the rainwater from our extension just drops down onto the concrete ground and through cracks in that, into our house (at the back of where their lean-to was). There is nothing on the deeds about sharing drainage but we have old Rightmove photos that show their old lean to and the guttering running along from us and along their lean to.
This concrete ground where their lean to way is also higher than the floor in the room that is getting damp
Where do we stand with telling them to fix the flashing? And what about the rainwater gutter that runs into nothing? Can we insist they install a water butt, for example? Or allow us to link back up to their drain? We will eventually be having works done on our extension so we can do temporary measures now but will need a long term fix too. Just wondering where we stand with them.