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Building upto neighbours extension that is build upto party wall line

Our neighbour has a rear extension that is built up to the party wall line, it has another interior wall creating a cavity on their side too, how do we go about building up against it. Can I build up to the party wall and just use the party wall as my interior wall or do I need to add another course of brickwork somehow inside my boundary line to make my interior wall, this making 3 courses of brickwork between the properties. If I need to add another wall how do I dig the foundations next to the existing foundations without undermining my neighbour’s extension in the process. Does this mean also that I could end up have to build my extension well inside my boundary and not up to the party line, just so I disturb their extension in anyway.

2 Answers from MyBuilder Extension Builders

Best Answer

It is best to have a chat with your neighbour first and try to work with them on the plans, decide how the roofs are going to meet


Answered 18th May 2015

you will have to dig down to their foundation line and go from there under the advice of your building control officer.You will probably find their foundation wont encroach into your land. dig around their footing and slightly under it as so your concrete supports it. regards using their wall as you exterior wall all you should have to do is build a internal skin of blockwork. as mentioned above the 3 skins of brickwork.


Answered 8th Nov 2012

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