Class Q permitted development allows agricultural buildings to be converted into homes without a full planning application — but only if the building meets strict eligibility criteria and you obtain Prior Approval from the council. Here’s how it works.
Class Q of Part 3, Schedule 2 to the GPDO 2015 allows the change of use of an agricultural building to a dwelling (or up to 5 dwellings from a single building) without a full planning application. You must apply for Prior Approval — a streamlined consent process where the council assesses specific issues (transport, noise, contamination, flood risk, and design). The building must have been in lawful agricultural use before 20 March 2013, and extensive rebuilding is not permitted.
Class Q (Change of use of an agricultural building to a dwellinghouse) was introduced in 2014 and significantly expanded in subsequent amendments. It falls under Part 3 of Schedule 2 to the GPDO 2015, which deals with changes of use.
Unlike Part 1 permitted development rights for houses, Class Q always requires a Prior Approval application. Prior Approval is a form of consent where the council can only assess the specific matters listed in the legislation — it cannot refuse on general amenity grounds or raise issues outside the permitted scope.
Class Q has been used extensively to convert redundant farm buildings across England into rural homes. It has proved controversial in some areas, with councils concerned about the proliferation of rural dwellings on agricultural land without normal planning scrutiny.
A Prior Approval application is submitted to the local planning authority and typically requires: a site location plan, existing and proposed floor plans and elevations, a statement demonstrating eligibility, details of any structural works, a transport and access statement, contamination assessment, flood risk assessment if relevant, and a noise assessment if needed.
The council has 56 days to determine a Prior Approval application. If it doesn’t respond within this period, approval is deemed to be given. The council can only refuse on the specific matters it’s permitted to assess.
| Parameter | Limit |
|---|---|
| Maximum number of dwellinghouses from a single building | 5 (or 3 where the building exceeds 465m²) |
| Maximum floor space per dwelling | 465m² (gross floor area) |
| Maximum total floor space for all dwellings on the agricultural unit | 865m² |
A single large agricultural building can therefore be converted into up to 5 separate homes, provided each is no more than 465m² and the total across the unit doesn’t exceed the cumulative limit. In practice, most barn conversions under Class Q create 1 to 3 dwellings.
Class Q permits both the change of use and certain building operations to convert the building. The permitted operations include: installation of windows, doors, rooflights, and solar panels; insulation; installation of services; partial infilling of openings; creation of internal walls; and reasonable external alterations needed for residential use.
Structural rebuilding of the main structure, creation of significant new floor area, and extending the building beyond its existing footprint are not permitted. Class Q is a change of use right, not a rebuilding right.
Extensions, loft conversions, outbuildings, solar panels — our complete guide covers everything you can build without planning permission.
Maximize your property’s footprint with precision and ease. Permitted provides complete design for Permitted Development Rights, ensuring your project meets all national requirements while bypassing the lengthy full planning permission process.
