Converting an agricultural building to a dwelling (Class Q)

The change of use of a building from agricultural to a dwellinghouse is permitted under Class Q of Schedule 2 of the Town and Country Planning (General Permitted Development) (England) Order 2015. A Class Q permitted development covers the changing of use and the building operations necessary to convert the building.

Class Q permitted developments do not need planning permission, but they do need prior approval. The change of use is still subject to a number of limitations and conditions, all of which must be complied with in order for a development to be allowed.

These conditions include submitting an application before beginning a development. This allows us to determine whether prior approval is required for any element.

What to include in your prior approval application

The basic requirements for a prior approval application are:

  • A written description of the proposed development, which must include any proposed building works or other operations
  • A plan indicating the site and showing the proposed development
  • The developer’s contact details
  • If in Flood Zone 2 or 3, a site specific flood risk assessment
  • The correct fee. For a development which comprises a change of use only the fee is £80, for any development which includes external alterations the fee is £172.

We strongly recommended that if any supporting information, such as contamination and structural reports, is needed to support an application it is submitted with the original application. This will prevent any undue delays in the consideration of the application and may avoid the refusal of prior approval.

We have 56 days to consider the proposals against the criteria in Class Q. The 56-day period commences on the day immediately following the day on which either a valid application is received or all required information has been received. A prior approval application is not valid and will not be considered until the correct fee has been received.

Criteria to meet Class Q application

For a building to be eligible for Class Q planning permission, it must fit the following criteria:

  • The lawful use of the site must have been for agricultural purposes immediately before the change of use is undertaken. A site which formed part of a mixed use of agriculture and (non-agricultural) equestrian uses, or agricultural activities which do not form a trade or business (in the manner of ‘hobby farming’), would not benefit from the permitted change of use. Where the history of a site is complex or ambiguous it is recommended that a statement setting out the nature of the previous use be submitted as part of the application.
  • The cumulative floor space of the existing building or buildings must not exceed 450 square metres. It is not possible to reduce the size of the building through partial demolition in order to meet this threshold. The 450 square metre threshold includes all development proposed or carried out under Class Q. The calculation should include any new floor space to be created.
  • The cumulative number of separate dwellinghouses developed under Class Q must not exceed three.
  • The development should not include any external projections from the existing structure.
  • There are limitations on the external works that can be carried out under permitted development. If external works and new structural elements are required, prior approval may be refused. Our case officers can carry out site visits if necessary.
  • The site cannot be on Article 2(3) land, which includes conservation areas, the South Downs National Park and the High Weald Area of Outstanding Natural Beauty.
  • The site cannot be of special scientific interest, a safety hazard area, military explosives area, a scheduled monument or a listed building. If the agricultural building is within the curtilage of a listed building, it may be curtilage listed.
  • Development under Class Q must be completed within a period of 3 years starting with the prior approval date.

In order to ensure a consistent approach, the following guidance will be followed on all Class Q prior approval applications.

Transport and highways

In assessing transport and highway impacts, we will consider:

  • The consultation response from the Highway Authority
  • The historical level of vehicular movements associated with a site
  • Accident records in the vicinity of the point of access onto the highway network
  • Whether adequate visibility is, or can be, provided at the point of access

Noise impacts

If there is potential for noise disturbance from adjoining uses, for example, farm activities, highways, railway lines or other commercial uses, the impact of noise on future occupants should be considered.

If necessary, noise assessments and mitigation measures should be submitted as part of the prior approval application.

This condition is considered in 'Location and siting of the building', below.

Contamination risks

If you consider there to be any risks from contamination - for example, if there are any signs of oil spillages or historical or adjoining uses comprising chemical or slurry storage, it is advisable that you commission a contamination survey and report at the outset. This report should comprise a Desktop Study, Site Walkover and Preliminary Risk Assessment.

We will seek to overcome any residual concerns through conditions requiring the submission and approval of details at a later stage but prior to commencement and occupation of a development.

The responsibility for safe development rests with the developer and / or landowner.

Flooding risks

The Flood Zone of a site can be found through the Environment Agency and through the website.

If a site falls within Flood Zone 1 it is unlikely that the proposal would raise any flooding issues unless the area has critical drainage problems, which we would be notified of by the Environment Agency.

If a site is within Flood Zone 2 or 3, a site-specific Flood Risk Assessment (FRA) will be required as part of the initial prior approval application.

The FRA should demonstrate that the development is appropriately flood resilient and resistant, with safe access and escape routes where required, and that any residual risk can be safely managed, including by emergency planning.

We will consult the Environment Agency on proposals in Flood Zone 2 or 3 and take into account any comments made by them.

Location or siting of the building

Whether the location or siting of a building makes it impractical or undesirable for a dwelling will include reference to the following factors:

  • Means of access: A building with no or poor means of access to a road is likely to require a significant length of hard surfaced track to facilitate use as a dwelling. In these instances there would most likely be an unacceptable urbanising impact on the rural character of the area that would be difficult to mitigate or overcome, with a change of use therefore impractical and undesirable.
  • Servicing: If it is not apparent that the installation of services, such as electricity and mains water, would be relatively straightforward and feasible additional information should be submitted as part of the prior approval application.
  • Nature of adjoining use: This consideration partly overlaps with noise impacts of the development. If a proposed dwelling would be surrounded by active agricultural or commercial activities the impact on living conditions for future occupiers may be considered undesirable, due to harmful/objectionable odour, noise and disturbance. If this is the case consideration should be given as to whether an assessment of background noise levels and adjoining uses could inform soundproofing measures/alternative means of ventilation, and whether this would overcome any such concern. In the absence of noise assessments / supporting reports we will not seek to secure further details of such measures through condition, adequate details are instead required at the determination stage.

Design or external appearance of the building

Any external building operations must ensure that the dwelling, once complete, is clearly legible as former farm building in the landscape. This can usually be achieved through appropriate fenestration and traditional materials.

The introduction of an overtly suburban and domestic character will be resisted; this is particularly in respect of fenestration, where excessive symmetry or glazing expanse can erode the functional form and general appearance of the building.