Permitted Development on Rural Land: Polytunnels, Stables, Field Shelters and Outbuildings

Rural planning throws up the same hopeful question again and again: surely I can just put up a shelter, a tunnel or a shed on my own land? Sometimes you can. There is a real set of rights, called permitted development, that lets some rural buildings go up without a full planning application. But those rights are narrower than most people assume, they change from nation to nation, and one widely quoted England figure is now simply wrong.

This is a plain-English guide, not legal advice. Planning is devolved, the rules shift, and the fine detail turns on your exact land and situation. Always confirm with the current source and your local planning authority before you build.

First, two things almost everyone gets wrong

Before any size table is worth reading, two foundations decide whether you have rights at all.

"Agriculture" is a legal test, not a lifestyle. The agricultural permitted development rights sit in Part 6 of the planning order, and they only attach to what the law calls agricultural land, meaning land "in use for agriculture and which is so used for the purposes of a trade or business, and excludes any dwellinghouse or garden". So a smallholding run as a genuine farming business can qualify. A hobby plot that is not run as a trade or business may get no Part 6 rights at all. Buying a field does not, on its own, hand you any right to build on it.

Size decides which door you go through. In England and Wales the rights split by holding area. On 5 hectares or more you may build new (Class A). On at least 0.4 but under 5 hectares you may only extend or alter what is already there (Class B), not put up new buildings. Under 0.4 hectares there are no agricultural permitted development rights, so a full planning application is the route.

Permitted development is not the same as "no process"

Here is the part that catches people out. Even when a farm building genuinely is permitted development, you cannot just start pouring concrete.

For a new agricultural building you must first apply to the local planning authority for a determination as to whether their prior approval is needed for the siting, design and external appearance. They have 28 days to tell you. You must not begin the work until one of three things happens: they confirm approval is not required, they grant approval, or the 28 days pass with no decision. In England, once the building is substantially complete, you then have to notify the authority in writing within 7 days.

Miss that prior approval step and the building is not lawful, even if it would otherwise have fit every size limit. So treat "permitted development" as "a lighter process", never "no process".

The rules by structure, in England

Different structures follow different rules. This table is the quick view for England. The detail and the traps follow below.

Domestic outbuildings

If the structure sits within the garden of a house and is for a purpose incidental to enjoying that house, a shed, greenhouse, garage or even a domestic stable is usually permitted development. It must be single storey, with eaves no higher than 2.5 m and an overall height up to 4 m for a dual-pitched roof or 3 m for any other roof. Anything within 2 m of a boundary is capped at 2.5 m. You cannot cover more than half the land around the "original house". On National Parks, the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites the rights are cut back, and within the curtilage of a listed building any outbuilding needs permission.

New agricultural buildings on 5 hectares or more

This is Class A, and it is where the big 2024 change lives. On a holding of 5 hectares or more you may erect a building reasonably necessary for the farming of that unit, with prior approval, provided the ground area for livestock housing or for plant and machinery does not exceed 1,000 square metres, and any building erected, extended or altered does not exceed 1,500 square metres. Height is capped at 12 metres, dropping to 3 metres within 3 kilometres of an aerodrome. It cannot be within 25 metres of a trunk or classified road, and a livestock or slurry building must be at least 400 metres from a "protected building", meaning a home that is not part of your own unit. No dwellings, and nothing on a separate parcel under 1 hectare.

Extensions on 0.4 to under 5 hectares

This is Class B, and the headline is simple: you can extend or alter an existing agricultural building, but you cannot build a brand new one. The height must not increase, the cubic content can grow by no more than 25%, any new part must be within 30 metres of the original building, nothing may be within 5 metres of a boundary, and the extended footprint must not exceed 1,250 square metres.

Stables and field shelters for horses

Polytunnels

A polytunnel in a domestic garden usually needs no permission. On a commercial growing holding of 5 hectares or more it is generally treated like any other agricultural building, so it can be permitted development with the prior notification step. On a holding under 5 hectares you will most likely need full planning permission, because whether a fixed tunnel counts as "development" is decided case by case on its size, permanence and how firmly it is attached to the ground. You may see a figure suggesting anything over about 6 square metres kept in one place needs an application. That comes from one planning adviser's rule of thumb in Welsh guidance, not from statute, so treat it as illustration only and check locally.

Fences, gates and walls

For a domestic boundary you generally will not need permission if a new fence, wall or gate is no more than 1 metre high where it is next to a highway used by vehicles, or no more than 2 metres high elsewhere. Listed buildings and their curtilage are excluded, and an Article 4 direction or planning condition can remove the right.

The 2024 change you must not miss

Nation by nation

Planning is devolved, so the size caps, the minimum holding and the extra conditions all differ. This is the shape of it. Always confirm against your nation's current source.

In Wales, holdings over 5 hectares have permitted development rights to build up to 465 square metres of structures, subject to prior approval, and the 28 day clock and prior notification work much as in England. In Scotland, Class 18 of the Scottish planning order allows agricultural buildings up to 1,000 square metres, or 465 in certain designated areas, on land of at least 0.4 hectares, again with prior notification. In Northern Ireland the cap is tighter at 500 square metres, the holding must be at least 0.5 hectares, and the building has to sit within 75 metres of the main farm buildings.

The traps people fall into

• Assuming ownership equals a right to build. It does not, and hobby land that is not a genuine business may have no agricultural rights at all.
• Quoting 465 square metres for England. Out of date since May 2024.
• Treating prior approval as optional. It is a required step, and skipping it makes the building unlawful.
• Calling a horse setup "agricultural". Grazing may be, but stables, arenas and fixed shelters usually need permission.
• Forgetting the standing caveats. Designated land, listed buildings, scheduled monuments and Article 4 directions all cut or remove permitted development rights.
• Ignoring building regulations. They are separate from planning, and a building can need approval even when planning does not.

Before you build or sell: check these

1. Is your land genuinely used for a farming trade or business, not just a hobby? If not, Part 6 rights may not apply.
2. Which size band are you in: 5 ha or more, 0.4 to under 5 ha, or under 0.4 ha?
3. Which nation's rules apply, and have you used the current figure, not the old 465 for England?
4. Have you lodged the prior notification and waited the 28 days before starting?
5. Is the site on designated land, a listed building's curtilage, a scheduled monument, or under an Article 4 direction?
6. Is it really agriculture, or is it equestrian or another leisure use that needs full permission?
7. Do you also need building regulations approval?

When in doubt, check the current gov.uk, gov.wales, gov.scot or planningni.gov.uk guidance for your nation, and speak to your local planning authority before you spend a penny. A short pre-application chat is far cheaper than an enforcement notice.