England only. GPDO 2015, as amended 21 May 2024
Can you convert your barn under Class Q?
Class Q lets an agricultural building in England become a dwellinghouse without a full planning application, subject to prior approval. The rules were rewritten on 21 May 2024: up to 10 homes on a unit, each no more than 150 square metres, 1,000 square metres cumulatively, with the agricultural use test now pinned to 24 July 2023. Designations kill it outright, and so does needing to rebuild rather than convert. Answer eight questions to see where you stand.
150 m²
maximum floor space of any single dwellinghouse developed under Class Q
10 homes
cumulative maximum per established agricultural unit, and 1,000 m² of floor space
56 days
for the council to determine prior approval before you may begin
Question 1
Where is the building?
Class Q is a permitted development right in England only. Wales, Scotland and Northern Ireland have separate regimes.
What it does and does not check
- England only: Class Q of Part 3 of Schedule 2 to the GPDO 2015, as substituted on 21 May 2024
- The agricultural use test tied to 24 July 2023, and the ten year alternative
- Designations that block Class Q outright: listed buildings, scheduled monuments and article 2(3) land
- The size limits: 150 square metres per home, 10 homes and 1,000 square metres per unit
- What building operations are allowed, and the single storey rear extension added in 2024
- The prior approval process, its seven matters and the 56 day determination period
- Not covered: agricultural tenancy consents and Part 6 interactions are flagged but need a professional check
Class Q Checker is an independent information site operated by Ellul Solutions Ltd. It is not affiliated with any local planning authority, the Planning Inspectorate or any government department, and nothing here is planning or legal advice. It covers England only, and it cannot see your site: designations, use history and structural condition all have to be confirmed locally before you rely on a Class Q route.
Class Q conditions and limits, current text
Last updated
Every numerical limit and hard condition in Class Q as it stands today, after the 21 May 2024 substitution. If a source quotes 5 dwellings, 465 square metres or 100 square metre smaller dwellings, it is describing the old version.
Taken from the current consolidated text of Class Q of Part 3 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 on legislation.gov.uk, checked on the updated date above. Class Q was substituted with effect from 21 May 2024 by the Town and Country Planning (General Permitted Development etc.) (England) (Amendment) Order 2024, S.I. 2024/579, article 3. Paragraph references are to Class Q itself and to paragraph W of Part 3, which governs the prior approval procedure. No planning application fee is quoted here because fees are set by separate regulations and change: confirm the current figure with your local planning authority.
| Condition | The limit | Provision |
|---|---|---|
| Size of each new home | Floor space of any dwellinghouse must not exceed 150 square metres | Q.1(c) |
| Number of homes per agricultural unit | Cumulative total under Class Q must not exceed 10 dwellinghouses | Q.1(d)(i) |
| Total floor space per agricultural unit | Cumulative floor space must not exceed 1,000 square metres | Q.1(d)(ii) |
| Agricultural use date test | Site must have been part of the established agricultural unit on 24 July 2023, or for at least 10 years before development begins | Q.1(a) and (b) |
| Use since leaving the unit | No use for any non-agricultural purpose since the site ceased to be part of the unit | Q.1(b)(iii) |
| Agricultural tenancy | Not permitted where the site is occupied under an agricultural tenancy, unless landlord and tenant both expressly consent | Q.1(e) and (f) |
| New farm buildings under Part 6 | Blocked where Part 6 Class A(a) or B(a) development was carried out on the unit in the previous 10 years | Q.1(g) |
| Footprint | No extension beyond the existing external dimensions, other than the permitted rear extension and protrusions of up to 0.2 metres | Q.1(h) |
| The rear extension | Single storey, to the rear only, no more than 4 metres beyond the rear wall, eaves no higher than existing, no higher than the lower of the existing roof or 4 metres, on hard surface in place since 24 July 2023 or for 10 years | Q.1(i) |
| Permitted building operations | Installing or replacing windows, doors, roofs, exterior walls and services, plus partial demolition reasonably necessary to do so | Q.1(j) |
| Designations | Not permitted on article 2(3) land, SSSIs, safety hazard areas, military explosives storage areas, scheduled monuments or listed buildings | Q.1(k) to (n) |
| Space standard and access | Must be capable of complying with the nationally described space standard, and have suitable existing access to a public highway | Q.1(o) and (p) |
| Prior approval | Application required before beginning; development may proceed if not determined within 56 days | Q.2 and W(11) |
| Completion | Development must be completed within 3 years of the prior approval date | Q.2(4) |
- Under the current Class Q, a single dwellinghouse created from an agricultural building in England must not exceed 150 square metres of floor space, and no more than 10 homes totalling 1,000 square metres may be created within one established agricultural unit.
- Class Q is blocked entirely where the building is listed, is or contains a scheduled monument, or the site is on article 2(3) land, which includes National Parks, areas of outstanding natural beauty, conservation areas, the Broads and World Heritage Sites.
- Class Q development may begin if the local planning authority has not notified the applicant whether prior approval is given or refused within 56 days of receiving the application, and must be completed within 3 years of the prior approval date.
Cite this page
“Class Q conditions and limits, current text”, Class Q Checker, https://classqchecker.co.uk/ (updated 2026-08-14). Taken from the current consolidated text of Class Q of Part 3 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 on legislation.gov.uk, checked on the updated date above. Class Q was substituted with effect from 21 May 2024 by the Town and Country Planning (General Permitted Development etc.) (England) (Amendment) Order 2024, S.I. 2024/579, article 3. Paragraph references are to Class Q itself and to paragraph W of Part 3, which governs the prior approval procedure. No planning application fee is quoted here because fees are set by separate regulations and change: confirm the current figure with your local planning authority.
Want this checked properly before you spend money?
We'll introduce you to a planning consultant or rural architect who handles Class Q prior approval applications.
Common questions
What is Class Q permitted development?
Class Q of Part 3 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 allows a building on an established agricultural unit, or a former agricultural building, to change use to a dwellinghouse, with building operations reasonably necessary for the conversion, subject to conditions and to prior approval by the local planning authority. It applies in England only.
Does Class Q apply to my barn if it is in a conservation area?
No. Class Q is not permitted where the site is on article 2(3) land, which includes conservation areas, National Parks, areas of outstanding natural beauty, the Broads and World Heritage Sites. It is also blocked for listed buildings, scheduled monuments, sites of special scientific interest, safety hazard areas and military explosives storage areas.
What is the 24 July 2023 date in Class Q?
It is the anchor for the agricultural use test in the current rules. The site must have been part of an established agricultural unit on 24 July 2023. Where it joined the unit later, or ceased to be part of it later, a period of at least 10 years before development begins applies instead.
Do I need planning permission for a Class Q conversion?
Not a full planning application, but you must apply to the local planning authority for a determination as to whether prior approval is required, and you cannot begin until it decides or 56 days pass. Building regulations approval is a separate requirement and is not covered by Class Q.
Can a barn used for storage be converted under Class Q?
Usually not. Class Q is not permitted where, since ceasing to be part of an established agricultural unit, the site has been used for any non-agricultural purpose. Commercial storage, workshops, liveries and holiday letting all count against the building's eligibility.
How long do I have to finish a Class Q conversion?
Three years. Class Q.2(4) requires the change of use, and any extension or building operations, to be completed within a period of 3 years starting with the prior approval date.
Check it before you draw it
Eight questions against the current Class Q text. Most schemes fail on history or designations, not design.
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