2nd storey rear extension

27 Jan 2014
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United Kingdom
So I built a single storey rear extension. It projected 7m off the back wall to finish flush with the end of my garage. The garage wall was used as a skin of my extension and therefore classed as a side extension, so I had planning and was completing under a building notice.

Now I have decided to do 2nd storey that will project 3m from the original house. Building control have said I can add it to the notice but would this be considered PD or would I require planning? And it’s going on top of something that’s yet to be signed off?
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The first floor rear extension would require formal Planning because the max. depth allowed under PD for a resulting two storey rear extension is 3m. But there are other PD rules also attached to that.

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Thanks for the reply.
So it doesn’t matter that my rear extension already has formal planning and the first floor extension isn’t going beyond the maximum depth of 3m?

You’re saying that when it’s both together, the max is 3m for both?

Do i have that correct? Thanks
It’s irrelevant as the ground floor element is still an extension and therefore not original. That’s like asking if you can add on a 3m PD extension to a 7m formal Planning extension.

In addition, is the existing extension within 2m of the boundary? Is the rear wall of the existing extension within 7m of the rear boundary?
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Yes I get what you are saying now but originally didn’t know whether the 2nd storey was just looked at by itself as being 3m and therefore ok and not together with the ground floor.

It’s within 2m of the side boundary’s but not 7m off the rear boundary.

So yes I clearly need formal planning. Thanks for the guidance.

I’ve been waiting on an architect to get back to me about a few things and he’s taking his time.
Nope as PD relates to the original and not extended dwelling. Obviously when you come to submit the formal application for the extension, the LPA will review exactly what you've applied for so the ground floor element is neither here nor there. But I don't think that's the question you were asking anyway.

Btw, and even if the ground floor was "original", the first floor extension would not meet another one of the PD requirements, i.e. eaves no higher than 3m when positioned within 2m of the boundary resulting in formal Planning being required.

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