Access to my property for building works next door

LightFlare

whose wall is that on the left of the picture and what is it.

whilst I agree with you in principle - is all this about what looks like 6" that you cant access/use anyway (assuming the left hand wall is yours)

I would be checking what their roof drainage plan is as if that wall is on or over the boundary - then they def cant put any gutters on that side

bgy3jlh

The wall on the left is my garage wall.

There is no known boundary, hence why I was insistent that the fence remain. 

No, it's about the signed agreement that they keep all building to their side of the fence as per the plan that went through planning permission and I didn't object to. I only uploaded one picture - the rest of their extension wall is beside my driveway. So it would mean that they were building partially on my land (if the centre of the fence is taken to be the boundary line) and that the fence that currently makes a nice separation between their buildings and mine, is gone. What if someone in the future wanted to build up to the boundary line on my side as part of an extension? Some people do reduce driveway length to accommodate an extension.

These people have played dirty from the beginning - trying all sorts of tactics to pressure me first of all into believing that my understanding of the approved plans were wrong, then that I definitely don't need a party wall notice, then that I don't need a party wall award or my own surveyor. And this rogue party is the local council, who are supposed to work for me as well as for my neighbour.