Agricultural prior notification on holdings of five hectares

Agricultural prior notification under Part 6 applies only to agricultural units of five hectares or more. Below that figure a different and much narrower right applies, and below 0.4 hectares there is no agricultural permitted development at all. That threshold is the first thing to check, because a farmer who submits a Part 6 Class A notification on a four-hectare holding has made an application the council cannot determine.

What Class A of Part 6 permits

Class A of Part 6 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 permits development on agricultural land comprised in an agricultural unit of five hectares or more, where the development is reasonably necessary for the purposes of agriculture within that unit.

That covers the erection, extension or alteration of a building, and excavations or engineering operations such as tracks, yards and slurry lagoons. It does not cover a dwelling, and it does not cover buildings for uses that are not agriculture, which is where equestrian enterprises, farm shops and storage lettings come unstuck.

The words reasonably necessary do real work. The test asks whether the building is reasonably necessary for the agricultural activity carried on within that unit, at the scale it is actually carried on. Usefulness alone does not meet it. A council refusing on this ground will usually point to the absence of any evidence about stock numbers, cropping or storage requirements, so put those figures in the notification.

Size, height and proximity limits

The limits that most often bite are these.

• Ground area: a building must not exceed 1,000 square metres, calculated with any other building erected or extended under the class within the preceding two years and within 90 metres.
• Height: 12 metres generally, reduced to three metres where the development is within three kilometres of the perimeter of an aerodrome.
• Roads: no part within 25 metres of the metalled portion of a trunk or classified road.
• Livestock and slurry: buildings for accommodating livestock and structures for storing slurry or sewage sludge are not permitted within 400 metres of the curtilage of a protected building.

The 1,000 square metre aggregation rule catches farms that build in stages. Two 600 square metre buildings within 90 metres of each other and two years apart do not both qualify, and the second one needs a full application.

The prior notification procedure

Class A is not a prior approval regime in the Part 3 sense. The developer applies to the authority for a determination as to whether its prior approval will be required for the siting, design and external appearance of the building, or the siting and means of construction of a private way.

The council then has 28 days from receipt to respond. It may say prior approval is not required, in which case the development may proceed in accordance with the details submitted. It may say prior approval is required and then approve or refuse those matters. Or it may say nothing, in which case the development may proceed once the period has expired.

Two practical consequences follow. Submit a complete set of details, because what is approved or allowed by silence is what you submitted. And keep the proof of the date of receipt, since the 28 days runs from receipt rather than from validation. The general mechanics of these procedures are set out in our note on how the prior approval procedure actually works.

Siting, design and external appearance

The council's discretion is limited to the matters listed, which is narrower than a planning application but not as narrow as farmers sometimes hope. Siting can be used to move a building away from a boundary or a view. Design and external appearance cover the form, the cladding and the colour.

Submit a location plan, a block plan showing the building in relation to the holding and the nearest dwellings, elevations with dimensions, and a materials specification naming the profile and the colour reference. Dark green, juniper green and olive brown cladding are the usual requests in sensitive landscapes, and offering them at the outset removes the commonest reason for a prior approval requirement.

Where the site is in a National Landscape, a National Park or a conservation area, expect a closer look and a higher chance that approval will be required. Trees, hedgerows and any watercourse should appear on the block plan with distances marked.

Dimensions on the drawing should match the dimensions in the description. A notification describing a 999 square metre building with elevations that scale to 1,020 square metres invites a refusal that costs three months.

Buildings and works outside the right

The right does not extend to a dwelling, to buildings for non-agricultural uses, or to development on land used for forestry, which has its own class. Equestrian use is not agriculture for planning purposes, so a stable block for livery or riding is a full application even on a large holding.

Farm shops, processing beyond what is ancillary, and buildings let to third parties for storage all fall outside. A building erected under the class and then let for non-agricultural storage is a breach of the condition attached to the right, and it is one that neighbours report.

The right also carries conditions about restoring land and removing buildings where agricultural use ceases within a stated period, which should be read before construction rather than after.

What this means for a later conversion

Buildings put up under agricultural permitted development have restrictions on later conversion. A building erected under Part 6 after the relevant date cannot be converted to a dwelling under Class Q for a period of ten years from the date it was substantially completed.

That matters to any farmer planning a two-step route from steel frame to house. It does not work, and the ten-year clock is checked from aerial imagery and the notification record. The current position on residential conversion is covered in our note on Class Q barn conversions and the 2024 amendments.

Illustrative example: a 60-hectare arable holding needs an 850 square metre grain store, 60 metres from an existing 400 square metre building erected three years ago. The aggregation rule looks back two years, so the earlier building does not count and the new one is within the limit. The notification includes stock and tonnage figures showing the store is reasonably necessary, dark green cladding and a block plan with the nearest dwelling at 180 metres. The council confirms prior approval is not required on day 24.

Keep the determination letter, the submitted drawings and dated construction photographs together in one file. Ten years later, when someone asks whether the building qualifies for conversion or whether it was lawfully erected at all, that file is the whole answer.

Where a full application is needed instead

A full application is required where the holding is under five hectares, where any limit is exceeded, where the building is for a non-agricultural use, or where the council determines that prior approval is required and then refuses it.

None of that is a disaster. A well-evidenced agricultural building application succeeds regularly, particularly where it is supported by a short Planning Statement setting out the farm enterprise, the functional need, the siting options considered and the landscape response. Where the building is prominent, add photographs from the nearest public road with the viewpoints marked.

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 are lawful.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. Enter the farm postcode on PlanScope to see which documents an agricultural building proposal is likely to need.