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Party Wall Query - extension over garage

Postby stefan.nadiya » Tue Oct 28, 2008 6:59 pm

Hi all,

This is my first post on here. I have looked at the site for useful info in the past and now require something a bit more personal.

Firstly I will explain the layout of the houses and neighbours so you have a picture in your heads.

On the left side is one neighbour. Her house is a linked detached.(with ours) We both share the driveway and have a garage each side by side. Above her garage is a bedroom extension. The exterior wall to her extension is on the shared part of the garages. Our lead flashing cuts into this extension.

Then there is our garage with nothing above it, just a pitched roof.

After that is our house, a semi detached.

Then furthest right is our other neighbour, a semi detached with her driveway the other side. She also has a large extension on her house.

We are an expanding family and when we bought the house 3 years ago, it was more than ample for us. Now we require some extra space and given the current financial crisis, moving house isn't an option for us. My father in law is a builder and has offered to build the extension, subject to planning, building regs etc for next to nothing so it makes financial sense to add an extra bedroom to our property cheaply.

In our garage, some beams or similar have been put in place for nexts doors extention and re-cemented. This was before we bought the house.

As our neighbour on the left already has an extension, she has at some point had to enter our property in order to build the thing.

I have today casually told her that we are thinking about adding a 3rd bedroom above the garage. What were her thoughts?

She said that providing our extension does not touch hers and remains a linked detached then she does not have any problems or objections. She is concerned that attaching our extension to hers will devalue the property, bringing it down from linked detached status to townhouse status.

It seems like she can have her extension and not want me to have mine because she is concerned about the value of her house going down.

I know that the de-valuation of a property as not an excuse for her to object on the planning application side of things but I am confused about the Party Wall Act.

Under the Party Wall Act, can she refuse to allow me to use her wall to attach my extension to? Even though she has built hers on the party wall from garage level up.

Am I right in thinking that 1/2 of that exterior wall facing me belongs to me and I can make alterations at my expense? Including attaching my extension to it?

Once the extension is built, both properties would benefit from being warmer in the winter as there would effectively only be an interior wall separating the two, not two exterior walls.

Also, if there was a gap separating the two, how would I need to waterproof the gap? This is not really an option if I can help it because it would mean losing over 1 foot of floor space along 5.5metres of room!

I am looking at submitting some form of planning application by Christmas.

And advice and help would be most appreciated.

Thank You in advance

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Postby LCL » Thu Nov 06, 2008 8:58 pm


There are two principle issues here, the first is planning consent and the second is the Party Wall act.

Your neighbours can object to the proposals under the town and country planning act. This is their biggest opportunity to object successfully to your proposals.

You'll need building regulations approval too, but this is technical and does not affect your neighbours.

The second main issue is The Party Wall etc act 1996. If i have understood your description correctly, the neighbour has raised the party wall wihtin the garage to construct their gable end. Under the act you can enclose upon this wall but may need to pay your neighbour 50% of the cost you would have otherwise had to pay to construct the wall. Done properly you'll have a better finished extension.

While you can submit the planning application yourself, you cannot act for yourself under the Party Wall act. Your neighbour can dispute the works under the act but cannot stop you doing what is legally possible. they can appoint their own surveyor and under normal circumstances, you will be liable for their fees.

I hope this helps

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Postby TheDoctor5 » Fri Jan 23, 2009 8:29 am

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