Class Q is a permitted development right that allows some agricultural buildings to be converted into homes. Instead of a full planning application, you apply for prior approval: the council checks a limited set of matters rather than the whole principle.
The rules were widened in May 2024, so much of the guidance online is out of date.
What Class Q allows now
- Up to 10 homes from a farm's buildings
- A total of up to 1,000 square metres of homes, with no single home over 150 square metres
- A single-storey rear extension of up to 4 metres, but only on existing hardstanding
- Building works reasonably needed for the conversion: windows, doors, roofs, walls, services
The building must qualify
- It must have been part of an established agricultural unit on or before 24 July 2023.
- It must be capable of conversion as it stands. Class Q covers conversion, not rebuilding. If the walls and roof need replacing, or a new structural frame is needed, it isn't a conversion. A structural survey is essential.
- It needs existing suitable access to a public road.
- The new homes must be large enough to meet the national space standards.
Class Q doesn't apply to listed buildings, or on land such as conservation areas, National Landscapes (including Dedham Vale) and Sites of Special Scientific Interest. Some farms have also had the right removed by an Article 4 direction or an earlier permission.
What the council looks at
Prior approval covers specific matters only:
- transport and highways
- noise
- contamination
- flood risk
- whether the location or siting makes the change impractical or undesirable
- the design and external appearance
- natural light in the habitable rooms
Once approved, the conversion must be completed within three years.
When Class Q doesn't fit
If the building doesn't qualify, a full planning application may still be possible. The new national planning rules published in August 2026 support the reuse of existing buildings outside settlements in the right circumstances. See our page on barn conversions.
How we can help
We check whether your building qualifies, measure it with a 3D LiDAR survey, design the homes in 3D, and prepare the prior approval or planning application. We also arrange the structural, ecology and other reports needed.
Book a free home visit
Ben will visit the farm, look at the buildings with you, and give you an honest view of whether Class Q or a planning application is the better route.
Every site is different. This guide is general information, not advice on your project. For a straight answer about your property, book a free home visit: Ben will come and look, with no obligation.
Who'll handle your project: Benjamin Plunkett, our Managing Director and Planning & Heritage Consultant, is your point of contact from the first site visit to the decision. Charlie Plunkett MCIAT produces the drawings.
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