Outbuilding extension, planning permission

2 Jan 2022
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United Kingdom
Hi all.
looking for some advice as I'm struggling with what I need to do.
I have a outbuilding which looks like I needed planning permission due the size in height which I wasn’t aware of at the time.
I’m now looking to extend this outbuilding and will need building regs due to the size.
To comply with planning do I just need to submit a new planning application for it all?
I’m a little confused as half of it is already built, so would the built part need retrospective planning or can it all go on a new planning application?
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What is the size of the footprint (and the ridge height), now and as planned, and how near the boundary is it?

Is it to be used for sleeping accommodation?

The current foot print is just under 30m2.

Tying to double the footprint

no living inside

currently sites at just under 4m to the ridge on the boundary

the new proposed section will be 2.5m at the boundary

If the existing building has been there more than four years, or if its not contentious and likely to conform to current planning policy, you could just apply for the extension.

Otherwise you could either just apply for the extension, or apply for existing and the new as a single application to formalise both.

You should consider what local policies may impact both extensions and the likelihood of one or both being approved
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No reason in principle why you couldn't apply for the retrospective element and the new part together or separately, as long as the connection between the two is picked up by the lpa. They should advise what forms to use. The local planning authority would have to consider them separately, as they might wish to refuse one and not the other.

Tactically better to wait (assuming nobody is objecting/enforcing), and rely on the 4 year rule, and you will have a stronger case for the "extension". People will assume you have a business use in mind for that size of outbuilding.

Thanks for the reply’s

once these four years have passed, should I submit for the certificate of lawfulness, wait for this to complete then submit another application for the extension?

or can i submit one straight after the other, or would it be best to wait?

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I don't know whether your just over the pd limit because of distance from the boundary or ridge height or because you will be covering half your garden. All those things will affect the lpa's attitude, as well as local circumstances. Have all your neighbour's done something similar or are you in an area of outstanding beauty?

You don't need to submit an LDC because your are immune from enforcement action - in this case after 4 years, just keep a good record. The LDC is proof of immunity, in fact the equivalent of a planning permission, and would help when selling the property etc.

The proposed extension would probably cover around 25% of the garden so there’s a fair bit of garden left not to have.

there is one neighbour who has an outbuilding this size (proposed) but looks like it has been done some years ago

how can you prove something’s been standing for an amount of time? Would receipts be acceptable proof?
The council use annual ariel surveys

Receipts are not in themselves proof of anything

How long has the thing been up? Would it not be approved if you applied?

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