Class S: agricultural building to a school or nursery

Class S of Part 3 of the General Permitted Development Order 2015 lets a farm building become a state-funded school or a registered nursery without a full planning application, subject to a floorspace limit and prior approval from the local planning authority. Using Class S for an agricultural building to school conversion has one feature that catches people out immediately: the class permits the change of use only. Any building work, from a new entrance to a window opening, needs its own permission.

So Class S is the door, not the whole project.

What the class permits and the destinations

The permitted development is a change of use of an agricultural building, and any land within its curtilage, to use as a state-funded school or a registered nursery. A state-funded school for these purposes is one funded wholly or mainly from public funds, which covers maintained schools, academies and free schools. A registered nursery means one registered under the childcare legislation.

A private fee-paying school is not within the class. Nor is a college, a training centre, a nursery that is not registered, or a children's activity business. Those need a full application for a change of use, assessed against the development plan.

The curtilage point is useful and underused. Because land within the curtilage is included, outdoor play space, parking and a drop-off area within that curtilage can come with the change of use, although hard surfacing and structures may still be operational development needing permission.

Floorspace limits and the qualifying building

The class carries a cumulative floorspace limit on the building changing use, expressed in square metres in the Order itself. Measure it properly, from the current text, and measure the cumulative figure rather than the floor area of the single room you intend to use first.

The building also has to qualify. The usual requirements are that it was in use solely for an agricultural use as part of an established agricultural unit on the date specified in the Order, or when last in use if it was not in use on that date, and that the site is not occupied under an agricultural tenancy unless the tenant and landlord have both consented. Where other classes in Part 3 have already been used on the same unit, that can also affect what remains available.

Paragraph S.1 of the Order lists the exclusions, and the Part has been amended more than once. Read the current text for the designations and conditions that apply to your site rather than relying on a summary of any vintage.

The agricultural use date requirement

Evidencing the agricultural use is where these applications most often fail, for the same reasons they fail under Class Q. The authority wants documents, not recollection.

What tends to be accepted: dated aerial photography, Rural Payments Agency field data and subsidy records, livestock movement records, feed and veterinary invoices addressed to the holding, agricultural tenancy agreements, farm accounts, and sworn statements from the farmer or a neighbour where documents are thin. A single statutory declaration on its own rarely persuades.

A building converted to storage for a non-agricultural business, even informally, breaks the requirement. So does a building that has been standing empty since before the relevant date without a documented agricultural use before that. Our note on proving a building was in agricultural use sets out the evidence in more detail, and the same material works for Class S.

Prior approval and the matters considered

The application is for prior approval, made under the procedure in paragraph W of Schedule 2. The authority can only consider the matters the class lists, which for Class S are transport and highways impacts, noise impacts, contamination risks and flood risks.

Notice what is absent. There is no design or external appearance matter, because no building works are permitted. There is no consideration of the principle of a school in that location, no development plan policy test, and no assessment of educational need. Those are not available to an objector either, which surprises parish councils.

The procedure in paragraph W sets the timetable. The authority has 56 days from a valid application, and if it fails to give a decision within that period the development may proceed in accordance with the application. Do not treat that as a plan. A deemed outcome leaves you without a written approval to show a funder, an insurer or the Department for Education.

Transport, noise and contamination

Transport is the matter that decides most of these applications. A school generates a concentrated arrival and departure pattern on roads designed for tractors, and the issue is usually the lane rather than the site. Submit a Transport Statement with trip generation, a school travel plan in outline, visibility splays at the access measured against the relevant standard, and a drop-off arrangement that keeps vehicles off the carriageway.

Noise runs in both directions. Children at play in the open is noise affecting neighbours, and the authority will want it assessed where dwellings are close. Equally, an existing farm, grain dryer, poultry unit or busy road can make the building unsuitable for a school, which is noise affecting the development. A Noise Impact Assessment should cover both directions explicitly.

Contamination is a real issue in farm buildings, more so than most applicants expect. Pesticide and herbicide stores, sheep dip, fuel tanks, asbestos cement sheeting and lead paint are all common, and the receptor here is children. Where there is a reasonable possibility of contamination, the authority will expect a desk study and, where the desk study identifies risk, intrusive investigation to the relevant standard by suitably qualified people. A contaminated land assessment is the document that does this, and it is the one to start early because the investigation takes weeks.

Flood risk and the change of vulnerability

This is the trap in Class S. In the flood risk vulnerability classification, an agricultural building sits in a low vulnerability category while a school sits in a more vulnerable one. So a change of use can move the building up the classification without altering a brick.

In Flood Zone 3a a more vulnerable use requires the Exception Test, and in Flood Zone 3b it should not be permitted at all. Because flood risk is one of the matters for prior approval, the authority can refuse on that ground. Check the flood zone before anything else, and where the building is in Zone 2 or 3 commission a Flood Risk Assessment that addresses the change in vulnerability, safe access and egress, and finished floor levels.

Surface water is the quieter problem. Hard play areas and parking increase run-off, and that work needs permission anyway.

Putting the prior approval submission together

A submission that gets determined rather than returned usually contains: a site plan with the building and curtilage outlined, floor plans with the floorspace calculation shown, the agricultural use evidence, the transport statement and travel plan, the noise assessment, the contamination desk study, a flood risk assessment where the zone requires it, and a short covering statement that takes each prior approval matter in turn.

Then submit the separate application for the building works alongside it. Running the two together is slower on paper and faster in practice, because the authority sees the whole project and the works application can be determined against the same evidence base.

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 only formal way to confirm that works or uses are lawful.

To see which of the 66 report types a conversion like this is likely to need, enter your postcode on PlanScope and answer the guided questions about the building and its constraints.

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.