boundry wall issue

we live in a terrace.we are building an extension back and front of the house.we are builing 150cmback from mid line of the boundry line.there are existing boundry walls back and front.we took the back boundry wall down to put in foundations and we will need to plaster the outside of the house.the back wall was in a poor state n was crumbling when foundations being dug.now our neighbour has decided he did not want it taken down.we have sais we will rebuild after our plasterer finishes our side..
what happens in these circumstances and we still have the front wall to take down!!
it also seems his sewers are attached to our mains within our boundry..what are we to do?

Please do not cross post in multiple forums

Clarify this for me, would you?

Are you saying you took down a boundary between the houses without agreeing this with your neighbour beforehand, or if you did agree it, without getting it in writing?

Whatever about building out the back and perhaps not needing permission, you need permission for anything out the fron over and above a 2.0M porch.

Even in the back you cannot reduce your open space below 25 sqm without permission.


ONQ.

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