Use Classes Which Use Class is my building? Directory of Uses Use Class B Use Class C Use Class E Use Class F1 Use Class F2 Sui Generis Use Class Timeline

Which use class is my building?

‘Which use class?’ is a very common question that many ask on a regular basis. This page will hopefully dispel some of the myths and maybe save a few phone calls in the task of answering the question of how to find the use class of a building.

It may easily fall into one of the six use class categories – Use Class B, Use Class C, Use Class E, Use Class F1, Use Class F2 & Sui Generis. But what happens if it doesn’t quite fall into one of these use classes or you are unsure as to which use class?

What is the planning unit?

A use class is normally linked to a planning unit.

Where ‘what use land and buildings have been put to’ is being considered, it is first necessary to determine whether there is a single planning unit or multiple planning units.

Mr Justice Bridge in Burdle v Secretary of State for the Environment [1972] 3 All E.R. 240 it was held that the planning unit is usually the unit of occupation, unless a smaller area can be identified which, as a matter of fact and degree, is physically separate and distinct, and occupied for different and unrelated purposes. The concept of physical and functional separation is key, and Justice Bridge suggested 3 broad categories of distinction:

1. Where it is possible to recognise a single main purpose of the occupier’s use of his land to which activities are incidental or ancillary, the whole unit of occupation should be considered the planning unit
2. Even though the occupier carries on a variety of activities, and it is not possible to say that one is incidental or ancillary to another, the entire unit of occupation should be considered the planning unit, in mixed use
3. Where there are 2 or more physically separate and distinct uses, occupied as a single unit but for substantially different and unrelated purposes, each area used for a different main purpose (together with its incidental and ancillary activities) ought to be considered a separate planning unit

Therefore it is quite possible for ancillary or incidental uses to come within the main planning unit. 

Can I call the Planning Department / Local Authority / Vicar?

Okay, maybe not the Vicar, but there is no point in phoning anyone to ask which use class!  Although maybe the Vicar can help if it is a church? The simple fact is that there is no list held by anyone.

There even used to be a rather poor app that was supposed to give you the use class of any building – it can’t. No app can – it can guess, but that is all it is, a guess. Please do not reply upon it. There is no list.

If the local authority says ‘put in a pre-app and we will tell you’, don’t. There is no list! Even previous planning applications given by the LPA is no guarantee, as the application may not have implemented the permission. Hopefully that is the most common myth dispelled. So if you want to know which use class is my property – don’t ask the local authority! No really – please don’t. I have had clients inform me that the local authority said X when I have told them it is Y and proved it!

Okay, so no list – but how can I tell which use class?

To perhaps answer the question of which use class, this is where you need to be a cross between Sherlock Holmes and Miss Marple. You will need to prove it yourself or with the help of your friendly planning consultant.

• What was the building used for when it was open?
• Look at Google Street View and go back in time via the small clock in the top left of the screen. Are there any A boards or other signage that will help? Make a note of the dates.
• Look up the building on the Valuation Office Agency (VOA) website – how does that describe the building for business rates? Maybe check more than one year if applicable?
• Ask neighbours to the building – can they help?
• Can you obtain any old leases or other agreements to support your case?
• Did anyone work there – local Facebook groups might help?
• Was it owned by a public body? If so try a Freedom of Information (FOI) request.
• Are there any planning applications for a previous change of use? Although note that previous planning on its own is no guarantee as you are not obliged to enact any planning permission.

As you can see from the list above, and there may be other sources of information, you may need to be able to prove which use class. If the local authority isn’t keen on the conversion under the GPDO they might be inclined to refuse it as they feel that it wasn’t what you think it was.

I think I now know which use class it is – or do you?!

Great!  However before you submit your application, there are a couple of reasons why it might not be what you think it is!  Is the unit ancillary to another building or another section of the building. A section of offices might actually be B2 because they are ancillary to a factory unit adjoining the offices.

I have known offices to be B2 with no units even close by, because the inspectorate ruled that the offices were ancillary to a unit in another town making pharmaceutical products! If the section can be shown to be a separate planning unit from another part of the building then you may well be fine. This is where a good planning consultant should be able to help.

Where a property is in two use classes – then it will be classed as sui generis. The one exception is a building with Class E, sub-paragraph (g) & B2 use as long as the section allocated to B2 is not substantially increased.

Some planning applications might have placed the property straight into sui generis. For example Class R could be a sui generis office.

It’s been empty for a long time, but I’m confident of which use class – all okay now?

Maybe, maybe not!  Sorry!  Has the building been abandoned? If it has then it will have no use class and full planning will be required. Obviously if the building is demolished the use class will also cease.

But how long is long enough to be abandoned? The issue here is that there is no set period of time. If a property is derelict, has no utilities and needs to be totally rebuilt then it is likely that it may well be considered abandoned and have lost any use class. If it has been left for ten to fifteen years you might be fine – but again there is no period set out in planning law to my knowledge. So the state of the building will probably come into play. Are you getting closer to which use class?

Not abandoned, I think I can prove which use class – what now?

Great!  Well done!  Either go ahead and submit your planning application as required along with any evidence required or maybe request from the local authority a Certificate of Lawful Existing Use (CLUED)  to prove that the existing use as you have identified is legal. In some circumstances a Certificate of Lawfulness of Proposed Use or Development (CLOPUD) might be applied for instead. See our page on Lawful Development Certificates for more.

Eek!  I still need help…..

Still confused as to which use class? No worries – book a session with Ian, the founder of Planning Geek and he will assist you via Zoom on both the building and also what you can do with it. You can book a session via this page.

Which Use Class – Page Updated: 11th April 2025

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