Applying for Change of Use When Renovating and Extending

Author: Chris Hogan

If you are renovating or extending a property where some or all of it hasn’t previously been used for residential purposes, then you will need to apply for what is called ‘change of use’ at the local planning office. This won’t affect the majority of extension builders, but all those who are considering renovating an old church or chapel, barn or agricultural building, or any other old non-residential building, will need to tackle this issue.

Introduction to ‘Change of Use’

Whether or not this is going to be a big problem for a specific case is very hard to say. Whether or not your change of use will be agreed depends completely on the rules in force where you are, the historical and architectural significance (if any) of the building and any specific restrictions arising from the local plan.

What we can do here is describe what a change of use application entails and the way that the planners will go about approving or rejecting it. Note that change of use applies to land as well as buildings. So if you are going to be extending onto land that, is currently agricultural, for example, you will need to apply for change of use before you can start.

As with most other bureaucratic processes to do with extension building, the change of use is dealt with by the local planning committee, under the guidance of the local planning office. The first step is to discover what use the building is currently registered for, and if there’s no registered use, get the planners to decide what it should be.

Categories of Use

There are a number of classes and sub-classes of use and the government’s planning portal can give a complete breakdown. The main categories are:

A: Mainly shops, restaurants and pubs, high street offices.
B: Industrial, storage and distribution, and other businesses.
C: Hotels, residential buildings and domestic dwellings.
D: Non-residential institutions and buildings for assembly and leisure.
Sui Generis (‘unique’): anything that doesn’t fall in to one of the above four classes.

Some change of use is permitted within these classes and again the planning portal can list these for you. However none of them include change from classes A, B or C to class D, which is what you will want, so an application will be necessary whatever the current use.

Planning Permission Checker

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Submitting the Application

Make the application to the local planning office with full details and reasons for the change. They will help with the precise process and the forms to fill in for their area. The planners will look at it with respect to national guidelines, the local plan and then the immediate area around the property.

But they will also take notice of general trends too. For example, in many areas of the UK, getting consent for change of use for a barn to a residential extension will not be a particular problem.

Your situation may be slightly different. ask a question below ↓ and our editorial team will reply with our advice.

Trends in Development

But over the past decade or so planners have begun to refuse these in some rural and semi-rural areas as they consider that it is making it hard for jobs to be created or sustained. It is now therefore easier to get change of use to offices or light industrial spaces instead.

This is why it is so hard to give hard and fast rules as to what change of use might be acceptable in any given situation. While planners are happy to consult and advise you, the only way to find out for sure is to make that application.

A Minefield for Development Projects

One final point of note. If you are embarking on a development project and there is likely to be a change of use issue, make sure you put the property subject to all planning consents being granted. Then if those consents don’t come through, you can legally back out of the deal.

And if the property is only for sale unconditionally, i.e. the vendor will not accept a sale subject to those conditions, it normally means the vendor has tried and failed to obtain those consents. So get the barge-pole out, and steer well clear.

The Next Step

Now that you have read through the advice above, you might want to put it into practice. Our Planning Permission Checker lets you tell us about your planned extension and find out whether you need planning permission or can build under permitted development. Try it now →

17 questions

Ask Extension Build a Question

Passive income strea 17/02/2020 at 6:49 am

I have a garden office (insulated and double glazed etc) in my back garden. It was erected in 2007. I would like to apply for change of use to independent separate use so that I may rent it out. (It has its own access). Do I get certificate of lawful development and then apply for change of use? How much would this cost and what is the likelihood of success?

Sandy 12/06/2019 at 4:15 pm

I'm interested in buying a piece of land in Scotland with full building rights ,it has two wooden chalets on all ready ,if I decided not to build but wanted just to live in one chalet and let other out as holiday chalet can I still do this ,they are log cabins at moment.

Sparkie 08/04/2019 at 5:19 pm

I've built a 2 storey annex which is a 1 bedroom and I'm looking to turn this into a separate dweling to sell does any 1 have any ideas of where to start with this procedure? Its completely separate to the house

JC 30/01/2019 at 12:07 am

Hi everyone, I’ve recently purchased a mixed use property in my town centre, it’s a double fronted Café on the ground floor with 2 separate 2 bed flats above on Floors 1 & 2, (2 up 2 down) one accessed from the front and the other from the back. I’m renovating them within the rules of permitted development but was wondering if it would be feasible to join them at the first floor and make a 6 bed flat with shared occupancy? I’ve asked my architect about this and highlighted the positive point of there being 2 fire escape routes if this was the case but he says it’s a change of use so would require planning and bringing upto current regs on sound insulation etc... long story, very expensive, not practical. No good. What would happen if I just did it but kept it as 2 separate for council tax and utilities etc?

ExtensionBuild Editor 16/03/2018 at 11:08 am

An annex can be sold/treated as a separate address without planning permission even though Council tax can treat it as such (it's an anomaly and councils usually avoid discussing it). Talk to your planning officer, they'll be able to give you help on whether you'll need to reapply or reinstate. They may also hint on likelihood of success (but aren't allowed to give you a definite answer of course).

AnnexQuery 15/03/2018 at 6:08 am

I have interest in purchasing a grade II listed property that has a separate stable block to its rear (unconnected to main house) which has lapsed planning permission to develop it into what the Decision report says is an “annex”. The plan would be to carve out a bit of the garden that has access to a road and parcel it up with the stable block so it is then put on a separate title to the main house. The stable block will have its own small garden, access to a road and own kichen, bathroom and so be self contained and physically separate to the main house. Does the reference in the Decision report to annex mean the lapsed planning permission cannot be a simple reinstatement of the permission and a full on new planning permission is needed to ask for the annex to be out on its own title? Council will presumably be fine with it being a separate dwelling on its own title as it gets council tax separate from the main house, but does planning see permission for an annex preempting the ability to out it on a separate title?

ExtensionBuild Editor 24/07/2017 at 12:06 pm

You will need planning permission for change of use and yes, your council tax will be affexted. Once registered as a separate dwellling it may be difficult to "unregister" it but you will probably be able to claim a council tax refund for an "unoccupied annex" if it's not in use. Note also that when you sell a property with a separated annex, the buyer has to pay extra stamp duty.

CAROLE 17/07/2017 at 3:52 pm

I am thinking of developing the bottom of my garden as an extra 2 bedrooms for my sons or to rent out.

Do i have to registered as an annex for both my sons use and to rent.

If it is treated as a separate dwelling how will that affect me, is it just that council tax will be expected.

If it was not in use is it a simply procedure to unregister the separate dwelling.

ExtensionBuild Editor 18/05/2017 at 12:53 pm

Check with your planning department about the likelihood of a holiday let. The re-sale value should only affect it if it's more likely to sell with a holiday let. If the separate annex is attractive to people with teenagers, elderly parents, it will still be a bonus. Chat to an estate agent in the area where the house is for sale to find out more about this (not the one who's selling it of course).

VIV 17/05/2017 at 2:01 pm

We have put in an offer on a property with a separate annex and want to use it as a holiday let. However we have just found out during conveyance that the annex has a planning condition on it (to be used only as ancillary use). The vendor says that we just need to apply for a change of use but we are really concerned. Should we get the barge pole out?
Is a property with planning restrictions on it worth less than one without? If so, any idea by how much? Does it work the same as it does with land? I.e land with permission to build is worth more than land without permission? Thank you.

ExtensionBuild Editor 04/05/2017 at 12:11 pm

You will need to apply for planning permission if it's to be used as a separate dwelling, distinct from the main dwelling. Once that's approved, you will need to register it with the Land Registry and the local council for council tax purposes and to register/obtain the new address etc.

BIFFO 03/05/2017 at 2:09 pm

We have recently had a extension built onto the side of our house,my son and family now live in the house and my wife and I live in the extension,the new build as been passed by the building inspector but we now wish to register it as a seperate dwelling please could you tell us what this involves and what would be our next step.

ExtensionBuild Editor 02/03/2016 at 12:06 pm

You will probably have to seek planning permission to do this as you are effectively changing the "nature" of the property.

Onesie 28/02/2016 at 6:09 pm

Can I open up the division between my annex and our main house thus including the annex space to be part of our main dwelling.

ExtensionBuild Editor 20/05/2015 at 2:31 pm

@Andibak. Check with your local planning office for the rules on outbuildings and permitted development in theses cases. The general rule is "the maximum height of 2.5 metres in the case of a building, enclosure or container within two metres of a boundary of the curtilage of the dwellinghouse."

andibak 17/05/2015 at 3:49 pm

I have a self contained cabin built at the bottom of my garden where my elderly father lives. It was built under Building Regs and was inspected by the council during construction. The building is 1 metre from my boundary with the neighbour. They are now going to build a garden room / office under building regulations which will be 2.5metres high right up to the boundary i.e. 1 metre away from the windows in my father's cabin. This will inevitaby block a lot of his light. Are they able to do this?

channy 21/09/2011 at 8:05 pm

So if I convert a 4 bed house into a residential care home for the elderly for 3 residents (this would require no structural changes) wouId I need to apply for change of use? If so, would it be a problem if I didn't?

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