Walkthrough: a new agricultural building on a holding
An illustrative walkthrough of a prior notification for a general purpose farm store, from the qualifying area test to the conditions that attach automatically.
A new agricultural building on a holding of 5 hectares or more usually goes in under Class A of Part 6 of Schedule 2 to the General Permitted Development Order 2015, which means a prior notification rather than a full planning application. The council is not deciding whether the building should exist. It is deciding, within 28 days, whether it wants to approve the siting, design and external appearance. That narrow question shapes everything about how the submission is written.
What follows is an illustrative walkthrough of one such notification on a mixed livestock and arable holding. The figures and the sequence are illustrative, and every holding differs.
The holding and the qualifying area
The unit in this example runs to 42 hectares in three blocks, with the farmstead at the centre. The proposed building is a general purpose store, 24 m by 15 m, with a ridge height of 7.5 m, sited to the north of the existing yard.
Three eligibility questions come first, and all three are answered before a drawing is produced.
- Is the agricultural unit 5 hectares or more? Class A applies only to units at or above that area. Below 5 hectares but at or above 0.4 hectares, Class B applies instead, and it is far more restrictive.
- Is the building reasonably necessary for the purposes of agriculture within that unit? A store for machinery used on the holding qualifies. A building for a contracting business working other farms does not.
- Does the proposal stay within the limits? Ground area of any building must not exceed 1,000 m², height is capped at 12 m, and 3 m applies within 3 km of the perimeter of an aerodrome.
At 360 m² and 7.5 m, the store sits well inside those limits. And the 5 hectare test is about the agricultural unit rather than the field parcel, which is the point most often misread by owners who have recently bought part of a farm.
What the prior notification covers
The application is an application for a determination as to whether prior approval will be required for the siting, design and external appearance of the building. The council can take one of three positions: prior approval is not required, prior approval is required and is granted, or prior approval is required and is refused.
The submission consists of a written description of the proposed development, a plan indicating the site, and the fee set by the national fee regulations. That fee is indexed annually on 1 April, so check the current schedule rather than a figure quoted in an old article.
The 28 day period matters. If the authority does not notify a decision within it, the development may proceed in accordance with the details submitted. That is a reason to submit a description precise enough to build from, because it is the description that becomes the permission by default.
Siting, design and external appearance
These three words are the whole planning argument. The submission addresses each in turn.
Siting is justified by function: the store sits beside the existing grain drying floor so that machinery movements stay within the yard rather than crossing the access track. It is set against the rising ground to the north, which puts the roof below the skyline when seen from the lane 400 m to the south.
Design is described in the language the officer uses: eaves at 5.4 m, ridge at 7.5 m, portal frame, gutter and downpipe discharging to an existing ditch, no rooflights on the southern slope.
External appearance is a materials schedule. Olive green profiled steel sheet to roof and upper walls, concrete panel to 2.4 m, timber boarding to the gable above the doors. Where the holding sits within a National Landscape or close to a listed farmhouse, the materials paragraph carries more weight than everything else in the submission.
| Element | What to state | Why the officer asks |
|---|---|---|
| Siting | Distance to yard, to boundaries, to nearest dwelling | Landscape effect and amenity |
| Height | Eaves and ridge separately | Visibility from public vantage points |
| Materials | Colour and finish of each element | Integration with the existing group |
| Access | Which existing access serves the building | Highway safety |
| Drainage | Where roof water and yard water go | Watercourse protection |
Access onto the public highway
Part 6 excludes development within 25 m of a metalled part of a trunk or classified road. Where a new private way is proposed, its siting is itself subject to prior approval.
In this example the store uses the existing farm access, which already has adequate visibility. That is stated in one sentence with the existing access marked on the plan. Where a new or altered access is involved, expect the highway authority to be consulted and expect visibility splays to be the question, which is the same test described in a walkthrough of a barn converted under Class Q prior approval.
Slurry, livestock and separation distances
Buildings for housing livestock, and structures for storing slurry, cannot rely on Class A within 400 m of the curtilage of a protected building, subject to limited exceptions for emergency replacement. A protected building means, broadly, a permanent building normally occupied by people, excluding buildings on the same agricultural unit.
That distance rule catches more schemes than any other part of Part 6. Measure it before designing anything.
Slurry and silage storage also carries separate regulatory duties on storage design and on notifying the Environment Agency before building or substantially altering a store, which sit outside the planning system entirely. Two regimes, two timetables, and the environmental one is not discharged by a planning approval.
The determination and the conditions that follow
The council in this example confirmed within 28 days that prior approval was required, and granted it with the materials as submitted.
Conditions attach automatically under Part 6 rather than being written by the officer. The building must be used for agriculture within the unit, the development must begin within five years of the prior approval date, and where the use ceases within ten years of substantial completion and no planning permission has been granted for other use, the building must be removed and the land restored. That last condition is the one that surprises owners who later want to convert the building, and it interacts with the ten year occupancy rule in Class Q.
The documents that went in
- A covering description of the development, with dimensions, materials and use.
- A location plan at 1:2500 with the unit boundary and the holding area stated.
- A block plan at 1:500 showing the building, the existing yard, the access and the 400 m radius to the nearest protected building.
- Elevations and a section at 1:100.
- A short statement on landscape effect, with two photographs from the lane.
Nothing more was needed. A prior notification is not a planning application, and a thick pack of unrequested documents invites questions the council was not otherwise going to ask. The contrast with a full application pack is visible in a walkthrough of a new dwelling in Flood Zone 2.
Where the holding later diversifies, the picture changes again, and the conversion route in a walkthrough of a shop to residential conversion under Class MA shows how differently a prior approval regime can be drafted.
This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. A lawful development certificate is the only formal way to confirm that works are lawful.
Enter your postcode on PlanScope to see which supporting documents a rural scheme on your holding 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.
Frequently asked questions
Does every farm building need planning permission?
Not where Class A of Part 6 applies. On an agricultural unit of 5 hectares or more, a building reasonably necessary for agriculture within that unit can proceed under a prior notification, subject to limits on ground area, height and proximity to roads and protected buildings. Units below 5 hectares fall under the much tighter Class B.
What happens if the council does not reply in 28 days?
The development may proceed in accordance with the details submitted, provided the notification was valid and complete. That makes the written description important, because it defines what you are then entitled to build. Keep proof of the date of submission and of any acknowledgement from the authority.
What is the 400 metre rule?
A building for housing livestock, or a structure for storing slurry, cannot rely on Class A if it would be within 400 metres of the curtilage of a protected building, subject to narrow exceptions. A protected building is broadly a permanent building normally occupied by people, not counting buildings on the same agricultural unit.
Can I convert the building to a house later?
Not automatically. Part 6 carries a condition requiring removal and restoration where the agricultural use ceases within ten years of substantial completion and no other permission has been granted. Conversion under Class Q has its own qualifying conditions, including how long the building has been in agricultural use, so the two regimes have to be read together.
Do I need to tell the Environment Agency about a slurry store?
Yes, separately from planning. Rules on storing silage, slurry and agricultural fuel oil require notice before a new store is built or an existing one substantially altered, along with design and capacity standards. A prior approval from the council does not discharge that duty, and the two timetables run independently.
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.