Part 3 Class S: farm buildings to a school or nursery
Class S of the GPDO allows an agricultural building to change use to a state-funded school or registered nursery, subject to prior approval. It permits no building works at all, which ends most projects.
Part 3 Class S of the General Permitted Development Order 2015 lets you change the use of an agricultural building, and the land in its curtilage, to a state-funded school or a registered nursery without a full planning application. Agricultural building to school permitted development is attractive on paper and narrow in practice: a 500 m² cumulative floorspace cap, a prior approval application covering transport, noise, contamination and flooding, and no building operations at all. That last point ends more projects than the floorspace cap does.
If the barn needs new windows, a new door, a raised floor or a roof covering replaced, Class S does not authorise any of it.
What Class S permits
The class permits development consisting of a change of use of a building, and any land within its curtilage, from an agricultural building to use as a state-funded school or a registered nursery. It is a use class change only.
Compare that with the residential conversion class, where works reasonably necessary for the conversion are expressly included. The difference is deliberate, and it is what you establish on site before anything else. Anyone who has argued about what counts as reasonably necessary structural works under Class Q will recognise the distinction immediately, because Class S gives you none of that latitude.
In practice that means two applications on most barns: the Class S prior approval for the use, and a separate full planning application for the physical works. Some applicants run them together. Others get the use established, then apply for alterations, which has the advantage that the principle of the use is settled before the design argument starts.
State-funded schools and registered nurseries
The definitions are specific. A state-funded school means a school funded wholly or mainly from public funds, which brings in academies and free schools as well as maintained schools. A registered nursery means early years provision registered under the childcare legislation.
A private fee-paying preparatory school is not a state-funded school. A childminder operating from a dwelling is not a registered nursery for these purposes. Establish the funding and registration status before anything else, because an application made on the wrong footing is invalid rather than merely weak.
Registration itself is a separate process from planning. You will need the inspectorate registration, and the early years foundation stage framework sets minimum indoor space per child by age band, currently in the region of 3.5 m² for children under two, 2.5 m² for two year olds and 2.3 m² for children aged three and over. Take the current figures from the published framework, then measure the barn against them before you commit to the site.
Floorspace and the agricultural use test
The cumulative floorspace of the building or buildings changing use under this class cannot exceed 500 m². That is measured across the established agricultural unit, so a previous Class S conversion elsewhere on the holding eats into the allowance.
The building also has to have been in agricultural use as part of an established agricultural unit on the qualifying date in the Order, or, if brought into use later, for the period the Order specifies before the change of use. Proving that is the same exercise as it is for a residential conversion, and proving a building was in agricultural use rests on the same documents: subsidy claims, livestock movement records, dated aerial imagery, invoices for feed or fertiliser, and a statutory declaration where the paper trail has gaps.
Where the land is let under an agricultural tenancy, the class is unavailable unless the tenant and landlord have agreed in writing. Get that agreement signed before the application, not during it.
What prior approval covers
The prior approval application under paragraph W of Part 3 asks the authority to approve a defined list of matters. For Class S those are transport and highways impacts, noise impacts, contamination risks and flooding risks. The authority cannot refuse on design, landscape impact or loss of agricultural land, which is the real value of the route.
| Prior approval matter | Evidence that usually settles it |
|---|---|
| Transport and highways | Trip generation for the roll, access geometry, visibility splays and a drop-off layout |
| Noise | Play noise at the nearest dwelling, and existing farm noise affecting the new use |
| Contamination | A desk study and, where it finds sources, intrusive investigation |
| Flooding | Flood zone check and a flood risk assessment where the site is at risk |
On a rural lane the transport evidence carries most of the weight, and a Transport Statement with a tracked drop-off layout answers the highway authority faster than correspondence does. Paragraph W also sets the procedure: the application with plans and the fee, consultation where the Order requires it, a site notice or neighbour notification, and a 56 day period. If the authority does not notify a decision within that period, the development may proceed in accordance with the application. That deemed consent is useful but fragile, so keep the correspondence and the date-stamped acknowledgement.
Contamination deserves particular care here. Children are a sensitive end user, former agricultural buildings commonly carry asbestos cement sheeting, buried fuel tanks, pesticide stores and sheep dip residues, and a desk study that misses one of those will be sent back. A land contamination assessment for this end use has to be prepared by a suitably qualified and experienced person working to the recognised investigation standard, and an AI-assisted draft is a starting point for that professional rather than a substitute for them.
Play space, parking and drop-off
Curtilage land is included in the change of use, so outdoor play space on the yard or an adjoining paddock within the curtilage is covered by the class. Hard surfacing, fencing, canopies and play equipment are building or engineering operations and are not.
Drop-off is where rural nursery applications fail. The traffic arrives in two 20 minute bursts, on a lane with no footway, and the highway authority will ask for a layout that keeps reversing off the carriageway and provides enough space that parents do not queue on the lane. Count the spaces properly: staff vehicles all day, plus parent vehicles during the peaks, plus a turning area a minibus can use.
Noise cuts both ways. Play noise is assessed against the nearest dwelling, and the farm's own noise and odour are assessed against the new sensitive use. A grain dryer running in September next to a nursery garden is a problem that a Noise Impact Assessment should identify before the application rather than after a complaint.
Exclusions and designated land
The class is unavailable where the building is listed or a scheduled monument, where the site is or forms part of a site of special scientific interest, a safety hazard area or a military explosives storage area, and where recent agricultural permitted development has been carried out on the unit within the period the Order specifies.
Designated land exclusions differ between the agricultural conversion classes and have been amended more than once, so read the current text of Part 3 against your site rather than relying on a summary, including this one. A conservation area, National Landscape or National Park designation may or may not remove the class depending on the version in force.
When a full application is unavoidable
Go straight to a full application where the building needs significant works, where the floorspace exceeds 500 m², where the roll is large enough to make transport a genuine policy question, or where the building is listed. A full application lets you present the whole project once, with a planning statement that addresses rural policy, the social infrastructure benefit and the transport evidence together.
It also lets you ask for more than the class allows, which on a school is usually the point: a hall extension, a staff car park, a hard play surface and a new access are all outside Class S.
This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it, and remember that a lawful development certificate is the formal way to confirm that a use or works are lawful.
Enter your postcode on PlanScope to see which reports a rural conversion of this kind is likely to need.
PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. For specialist technical reports, qualified professional input may be required.
Frequently asked questions
Does Class S allow building works as well as the change of use?
No. Class S permits a change of use of the building and its curtilage land only. New windows, doors, floors, roof coverings, hard play surfaces, fencing and canopies are building or engineering operations and need separate planning permission. This is the main difference from the residential conversion class, which expressly includes works reasonably necessary for conversion.
What is the floorspace limit under Class S?
The cumulative floorspace of the buildings changing use under the class cannot exceed 500 m², measured across the established agricultural unit. A previous Class S conversion elsewhere on the holding reduces what is left. Above that figure you need a full planning application, which also lets you include the works and any new access.
Which matters can the council refuse prior approval on?
For Class S the prior approval matters are transport and highways impacts, noise impacts, contamination risks and flooding risks. The authority cannot refuse on design, landscape impact or loss of agricultural land. Keep the submission focused on those four and provide evidence on each rather than a general planning case.
Does a private school qualify under Class S?
No. The class applies to a state-funded school, meaning one funded wholly or mainly from public funds, which includes academies and free schools, or to a registered nursery under the childcare legislation. A fee-paying independent school does not qualify and needs a full planning application for the change of use.
How long does the prior approval take?
Paragraph W of Part 3 sets a 56 day period from a valid application. If the authority has not notified its decision within that period, the development may proceed in accordance with the application. Keep the date-stamped acknowledgement and all correspondence, because relying on a deemed approval without records is difficult.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.