At The Rural Planning Co we gets lots of calls, enquiries and questions about Class Q development. To help you gain an understanding of this permitted development we have listed some of these below. This list is not exhaustive, please call us if you need any help and advice. Rural planning is what we do!

Class Q is a permitted development. It is part of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) and allows the conversion of agricultural buildings to dwellinghouses subject to conditions and limitations.

Put simply, it allows for a barn conversion without the need to apply for full planning permission, although there is still a requirement to apply to your Local Planning Authority.

It allows development consisting of the change of use of a building and any land within its curtilage (garden and parking) including the building operations reasonably necessary to convert the building, to use class C3 (dwelling houses).

There are lots of criteria that must be met for Class Q, starting with the building itself; how it has been used, where it is sited, and its physical construction.

The building must have been used solely for an agricultural use, within an agricultural unit, usually for the last 10 years. Class Q cannot be granted for buildings in Areas of Outstanding Natural Beauty, National Parks, Conservation Areas, if the building is listed, or if the site contains a scheduled monument.

The existing building must already be capable of conversion. This means that the building as it stands must be structurally sound, and capable of being turned into a dwelling without being completely rebuilt. Whilst building operations are allowed, if those operations are so substantial that they could be considered a construction of a new building then in this case the conversion would fall outside the scope of Class Q.

There are different floor area thresholds depending on the amount and size of the proposed new residential buildings. You can have up to five new properties within the agricultural unit in total. These can be “Smaller Dwelling Houses”, “Larger Dwelling Houses” or a combination.

Smaller Dwelling Houses have a floor space of up to 100m² and Larger Dwelling Houses are between 100m² and 465m².

So, to illustrate:

  • You can have up to three larger dwelling houses as long as the maximum combined floorspace does not exceed 465m²
  • You can have up to five smaller dwelling houses with a floorspace limit of 500m² (up to 100m² each)
  • You can combine the two as long as you do not exceed five units in total
  • The maximum possible combination is 865m²; one unit of 465m² and four units of 100m²

It is important to note that the development must be within the footprint of the existing agricultural building and the dimensions of the existing building cannot be extended. That also means that any insulation works must be done internally, and any further additions externally (even new guttering or a chimney flue) would require full planning permission.

For a Class Q or full Barn Conversion you should be budgeting £3000 to £6000 for the planning consultant dependent on the level of work that needs to be completed. On top of this you need to account for surveys and drawings which could cost between £3000 and over £8000. A reasonable total budget would be £6000 to £14000.

Whilst with planning you can never be guaranteed success, a good planning consultant will give you their thoughts on your chances of success. If you get approval to convert your barn from agricultural to residential use then this will ultimately increase the value of your asset.

As an example, dependent on the way in which you convert, a residential barn can have a rental value of over £30,000 per annum and a sale value of over £300,000. If you consider this, then the percentage of the planning cost is low.

Class Q was introduced in 2014 as a form of permitted development to help ease the pressure on housing in rural areas.

Class Q allows a route into developing homes in rural areas without having to meet an exception policy. It is also an option in areas where the Local Planning Authority does not otherwise support barn conversions.

In some cases, when compared to full planning permission, Class Q planning permission has a lower upfront cost, does not require quite the same level of technical detail as full planning permission does, and can be faster.

It is true that the amount of technical information required for the application isn’t as extensive as for a full planning permission application, but you will still need technical information on noise, contamination, flooding and more.

The criteria for Class Q are very strict and not all buildings will qualify. If just one of the criteria is not met then it will not be possible to get permission under Class Q.

Even if Class Q is approved, the consent is very restrictive, for example you cannot extend beyond the dimensions of the original building, and the area allowed for parking and garden and be no larger than the footprint of the building.

The scope of modification under this permission is limited to the existing footprint of the structure. Extensions beyond this footprint require full planning permission, which can be more challenging to obtain, especially in rural settings.

Not under the Class Q permission, but there are options which can be explored to reapply to the council for an alternative, improved development. This is often referred to as Class Q supersede.

The Q does not stand for anything in particular.

The permitted development rights classes can be found in The Town and Country Planning (General Permitted Development) (England) Order 2015. Class Q is one of many. Other examples include Class R – agricultural buildings to a flexible commercial use.

The barn or agricultural building must have been used solely for agricultural use for the last 10 years, or if not in use for that time, then when it was last used. It can’t have had any other material change of use, so if it has been used for horses then it probably won’t qualify. You can’t build a barn now and then convert it; it would have to be in use for 10 years first.

The existing building must already be structurally sound and capable of conversion. While building works are allowed, if these operations are so substantial that they could be considered a construction of a new building then the conversion would fall outside the scope of Class Q. 

There is no requirement for the building to be made of specific materials though – both modern and traditional buildings can be considered.

If a Class Q prior notification application is approved the applicant has three years to complete the conversion. This is different to full planning permission which usually contains a time limit to start the development.

An application has to be made to the Local Planning Authority for prior approval before any works can be done under Class Q. The Local Planning Authority are required to respond to these applications within 56 days.

Class Q is rather restrictive when it comes to land designations and does not permit development in National Parks, Areas of Outstanding Natural Beauty, Sites of Special Scientific Interest, Conservation Areas, if the building is listed, or if the site contains a scheduled monument.

If the site is occupied under an agricultural tenancy, Class Q can only proceed when both the landlord and the tenant have given their consent.

Class Q cannot proceed if an agricultural tenancy has been terminated one year before the development begins or for the purpose of carrying out the development, unless both parties agree that the site is no longer needed for agricultural use. 

Once a Class Q development has been granted, there are ways that it can be changed. Plans under Class Q can be amended, and in some circumstances, it may be possible to apply for full planning permission in place of the approved Class Q. This can give you much broader scope for the development and could even allow you to demolish the barn and construct a new dwelling.


Before considering this option, the Class Q has to be granted in the first instance. This Class Q then becomes the fall-back position.

With Class Q in place to give you a fall-back, it can be possible to supersede this with a much more flexible full planning application. This could be for the same design as that approved under Class Q, an improved design, or even a complete redevelopment including demolition of the barn and construction of a new-build dwelling.


There are several distinct advantages to doing this, some of which are;

  • The scheme could be redesigned to make better use of the site and provide a more attractive building and surroundings, for example, by changing the materials or allowing for a larger garden area.
  • You could carry out more building works than would be permitted under the Class Q. Or even make a new building larger than the approved Class Q.
  • There is scope to reposition a new building on the site if it will provide clear enhancement and betterment. Whilst a planning officer might not allow placing the new building a distance away from the existing, we have successfully gained approvals to reposition a building on a site.
  • If you are permitted to demolish the Class Q and construct a new build, the construction itself would likely be more efficient and would allow more use of modern building materials (particularly for energy efficiency).
  • Full planning permission would be subject to a condition requiring you to make a start on the development within a set timeframe, whereas a Class Q development must be completed within 3 years. This provides much more flexibility in terms of time to build out the development.
  • Whilst VAT on build costs is reduced to 5% on the conversion of agricultural buildings to residential, there is no VAT if you demolish the existing to build a new home.
  • If full permission is granted, that does not automatically take away the Class Q permission. You can choose which permission you want to implement.
  • If you have lots of barns to develop then by skipping to full planning permission, your Class Q rights can be effectively ‘opened up’ for use on other buildings again.
  • Class Q development rules are very strict. It can be easy to inadvertently go outside of what’s allowed, whilst carrying out your development, which could (in the very worst-case scenario) result in the entire permission being lost. Should that happen under full planning, there are more options to retrospectively make amendments – making it a safer option to develop.

Be aware that there can also be disadvantages.

  • CIL and affordable housing contribution payments may differ between Class Q development and full permission for conversion, or new-build – Local Planning Authorities will vary on this.
  • Applying for full planning permission can take time. Be careful not to run out of time on your Class Q in the meantime, as it must still be feasible to develop to give you the fall-back position (you can re-apply under Class Q to keep the clock ticking though).
  • There are generally more planning considerations under full planning permission as local policies come into play, so there may be more hoops to jump through for example design guidelines or restrictions.

The ability to supersede Class Q with full planning permission is very much dependent on the specific details of the site in question. However, we would always recommend considering following up Class Q with full planning, even if you don’t want to change the design, simply for the additional security that a full planning permission can provide.

Class Q does not allow building operations other than the installation or replacement of;

  • Exterior walls, roofs, doors, windows, or
  • Electricity, gas, water, drainage, or other services to the extent reasonably necessary for the building to function as a dwellinghouse

And, demolition is allowed to the extent reasonably necessary to carry out building operations listed above.

It’s important to note however that while the works listed above can be carried out, that’s not to say you can do all of the works – as that would likely result in a rebuild rather than a conversion.

It is worth reading the Government Guidance on Permitted Development Rights for the change of use of agricultural buildings.

Planning Permission is granted by the Local Planning Authority, which is generally a unitary, district or borough council, to carry out development. The grant of planning permission is underpinned by section 70 of the Town and Country Planning Act 1990, and requires consideration of national and local planning policies.

Permitted development rights are set out in legislation and are the government’s way of allowing for certain developments at a national level without needing to have full planning permission, so long as set criteria are complied with.

Some forms of permitted development require prior approval from the Local Planning Authority before they can be carried out. This process is similar to applying for planning permission, except the decision at the end is not technically a grant of permission, but a confirmation of compliance with set criteria which vary depending on the type of application.

The applicant is responsible for making sure that their development actually is permitted development, and it’s very important that the works carried out reflect the details that were submitted with the prior approval application. As the name suggests, prior approval cannot be given restrospectively!

If you meet the criteria for Class Q, a prior approval application can be submitted.

This looks at:

  • Transport and Highways impact of the development
  • Noise impacts
  • Contamination risk on the site
  • Flood risks
  • Location and siting of the building
  • Design and external appearance
  • The provision of natural light in all habitable rooms

The local planning authority will also assess whether they believe the development meets the permitted development criteria. You will likely have to submit extra supporting evidence with the application to prove compliance with criteria, such as structural surveys.+

The scope of modification under this permission is limited to the existing footprint of the structure. Extensions beyond this footprint require standard planning permission, which can be more challenging to obtain, especially in rural settings.

It is important to note that the development must be within the dimensions of the existing agricultural building and the roof cannot be raised. That means that any insulation works must be done internally, and any further additions externally (even new guttering or a chimney flue) would require further planning consent.

No, Class Q does not permit development in National Parks, Areas of Outstanding Natural Beauty, Sites of Special Scientific Interest, Conservation Areas, if the building is listed, or if the site contains a scheduled monument.

No, Class Q does not permit development in National Parks, Areas of Outstanding Natural Beauty, Sites of Special Scientific Interest, Conservation Areas, if the building is listed, or if the site contains a scheduled monument.

Different Local Planning Authorities have different approaches to how they assess Class Q’s, and as a result the success rates do vary. We continually monitor this across a range of authorities, so if you want to know the chances of success where you are then call 01299 667344 or email hello@theruralplanningco.co.uk for more information.

In most circumstances, yes, as the rules currently stand you can use a barn converted under Class Q for short term holiday lets.

No – there are no occupancy restrictions on Class Q or need for the dwelling to be occupied in connection with the farming business.

Generally, no. The prior approval process has to be carried out in advance of any works, and there is also a risk that if works have been done (depending on the extent of those works) then the building might no longer qualify as an agricultural building.

Class Q is a section of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended). This is a big piece of legislation which also covers a range of other matters, such as extensions to houses, and importantly here, the rights to carry out works necessary for agriculture under Part 6. Class Q and Part 6 do cross over – you can’t put up a new shed using your agricultural permitted development rights AND apply to convert a barn under Class Q within the same 10 year period. If you had full planning permission for a new shed however then there would be no impact on Class Q. This area of legislation can get complex so if you think you might be affected by this then ask a planning consultant to assess it for you.

The garden and parking area that can be included within the Class Q must be no larger than the footprint of the original garden i.e. if the barn has a footprint of 250m2, then the garden and parking can be no more than 250m2. You can apply for planning permission to extend this later.

Unfortunately, not always. Householder permitted development rights, which would usually allow you to do minor works to a house such as a small extension or porch, are removed from dwellings built under Class Q. This means you would have to apply for full planning permission from the Local Planning Authority and some areas can be quite negative about extensions to barns.