Do I need planning permission for a shed or garden building?

The height, area and position limits that keep an outbuilding within permitted development in England, and the situations where none of them apply.

Difficulty: beginner
Time: 20 min
Read: 4 min
Safety: caution

Short answer

For most houses in England, an outbuilding is permitted development if it is single storey, no more than 2.5m high within 2m of a boundary, no more than 4m to a dual-pitched ridge otherwise, covers no more than half the land around the house, and is not in front of the principal elevation.

Most garden buildings are permitted development, which means no application is needed. The exceptions catch people out badly: flats, listed buildings, conservation areas, houses where permitted development rights were removed by condition, and anything used as self-contained accommodation.

Safety

This is a general summary of permitted development for houses in England, not legal advice, and the rules differ in Scotland, Wales and Northern Ireland. Listed buildings, conservation areas, National Parks, Areas of Outstanding Natural Beauty and flats are all treated differently. Check with your local planning authority before building — a lawful development certificate is cheap compared with a demolition order.

Step by step

Check whether your home has permitted development rights at all.Flats and maisonettes have none. Listed buildings need listed building consent for almost anything. New estates often have permitted development rights removed by a planning condition — check the original planning decision for the house.
Check the location on the plot.The building must not be forward of the principal elevation — in practice, not in the front garden. On a corner plot the side elevation facing the road may also count.
Check the height against the boundary distance.Within 2m of a boundary, the maximum overall height is 2.5m. Further than 2m away, 4m to the ridge of a dual-pitched roof or 3m for any other roof, with eaves no higher than 2.5m.
Check the total coverage.All outbuildings together must not cover more than half the land around the original house, excluding the ground the house itself stands on.
Check it is not going to be a dwelling.Permitted development covers buildings incidental to the enjoyment of the house — a shed, a workshop, a home office, a summerhouse. Anything with sleeping accommodation and independent facilities is a separate dwelling and needs permission.
Check for designated land restrictions.In conservation areas, National Parks, the Broads, AONBs and World Heritage Sites, outbuildings to the side of the house are not permitted development and total area limits are tighter.
Consider building regulations separately.Planning and building regulations are different systems. A small detached outbuilding under 15 square metres with no sleeping accommodation is generally exempt; between 15 and 30 square metres it may be exempt if it is at least 1m from a boundary or built of non-combustible material. Electrical work is notifiable regardless.
Get it in writing if it matters.A Lawful Development Certificate from the council confirms the building is permitted development. It costs a fraction of a planning application and is exactly what a buyer's solicitor will ask for.

Tips

The 2.5m limit near a boundary is the one that catches people — it is very easy to exceed with an apex roof.
Deed covenants can restrict outbuildings even where planning does not. Check the title deeds as well as the planning rules.
If you plan to run power out to it, factor in the electrician's notification and certificate from the start.

Common mistakes

Assuming a garden office is automatically permitted development — It usually is, as long as it stays incidental to the house. Once it has a shower, a kitchen and someone sleeping in it, it is a separate dwelling and needs full planning permission.
Measuring height from the shed floor — Height is measured from the highest ground level immediately adjacent to the building, not from the base or the floor. On a sloping site this matters a great deal.

If it doesn't work

Building is 100mm over the height limit near a boundary

Cause: Apex roof close to the fence — Fix: Move it more than 2m from the boundary, choose a lower-pitch or pent roof, or dig the base down. All are cheaper than a retrospective application.

Neighbour has complained about a new outbuilding

Cause: It may or may not be permitted development — Fix: Check it against the limits honestly. If it complies, apply for a Lawful Development Certificate. If it does not, a retrospective planning application is the route.

Not sure whether permitted development rights were removed

Cause: Condition on the original estate planning permission — Fix: The council's planning portal holds the original decision notice for the house. Search by address and read the conditions.

Questions people ask

How big can a shed be without planning permission?

There is no single size limit — it is governed by height, position and the proportion of the garden covered. In practice, a single-storey building under 2.5m high, behind the house, and covering well under half the garden is almost always permitted development in England.

Do the same rules apply in Scotland and Wales?

No. Scotland, Wales and Northern Ireland each have their own permitted development rules with different limits. Check the relevant national guidance and your local authority.