HomeGuidesPlanning Permission for a Carport, Pergola or Shed

Planning Permission for a Carport, Pergola and Shed

Whether your carport, pergola or garden shed needs planning permission depends heavily on where you live — sometimes right down to the individual council. This guide explains the underlying principles across England, Wales, Scotland, Northern Ireland and the Republic of Ireland, and shows what to watch for with boundary distances and your local development plan.

First things first: this isn't legal advice — and what “permitted development” means

Whether your project needs planning permission is decided locally — sometimes right down to the individual council or even the specific plot. England, Wales, Scotland and Northern Ireland each run their own planning system, and the Republic of Ireland has its own rules again. This article gives you rules of thumb and the underlying principles so you know what matters. It is not a binding ruling. Before you dig the first hole, always check with your local planning authority — the advice is usually free and can save you an expensive tear-down later.

In all of these jurisdictions the logic is similar: small structures are often permitted development (England, Wales, Scotland, Northern Ireland) or exempted development (Republic of Ireland), or fall under a simplified prior-notification process. That means you don't have to submit a full planning application. It does not mean you can build whatever you like. Even a permission-free shed must still meet every substantive rule — boundary limits, the local development plan, conservation-area controls, listed-building and protected-species law. If you build under permitted development, the responsibility for getting it right rests with you.

The criteria that decide whether something is permitted development are much the same everywhere:

England & Wales: Permitted Development Rights

In England and Wales, most detached outbuildings — sheds, garden rooms, carports and pergolas — can be built under Permitted Development (PD) rights without a planning application. The headline limits are a maximum overall height of 4 m for a dual-pitched roof (3 m for any other roof) and a maximum eaves height of 2.5 m. Outbuildings must not sit forward of the principal elevation (the front wall) of the original house, and together they must not cover more than 50% of the land around it.

Structure (England & Wales)Allowed under PD up to approx.Applies to (simplified)
Detached shed / garden room4 m ridge, 2.5 m eavessingle storey, to the rear
Outbuilding within 2 m of a boundary2.5 m overall heightany roof type
Carport (open-sided)PD within the height limitsnot forward of the front wall
Pergola (open, no roof cover)usually PDcheck height if near a boundary
All outbuildings combinedup to 50% of the gardenland around the original house

The 4 m allowance applies only to a dual-pitched roof and only outside designated land. In conservation areas, national parks, the Broads and Areas of Outstanding Natural Beauty the limits are tighter — for example, no outbuildings to the side of the house, and a maximum of 10 m² for anything more than 20 m from the house. An Article 4 direction can also remove PD rights for a specific area, so always check the current position before you order materials.

Boundary distances and your local plan — the most common pitfall

Even when your structure is permitted development, its position relative to the boundary still matters. In England, Wales and Northern Ireland, any outbuilding within 2 m of a boundary is capped at 2.5 m in overall height; in Scotland the same cap applies within 1 m of the boundary. You can usually build right up to the line, but you must not build on — or let the eaves, gutters or foundations overhang — your neighbour's land, which is a civil trespass matter. If you build against a party boundary or excavate near a shared wall, the Party Wall etc. Act 1996 may require you to serve notice on your neighbour.

At least as binding is your local development plan (and any conservation-area designation). It can set out where you may build, the footprint, roof shapes, ridge and eaves heights, and sometimes even materials and colours. A quick look at the plan — on your council's website or planning portal — often tells you upfront whether your project is acceptable at all. An Article 4 direction or a restrictive covenant on the title can add further limits on top.

Scotland: permitted development and prior notification

Scotland runs its own permitted development classes. Outbuildings within the curtilage of a house are generally allowed without an application, with a maximum height of 4 m for a dual-pitched roof (3 m otherwise) and a 2.5 m cap where the structure sits within 1 m of the boundary. As in England, outbuildings must not extend forward of the front wall, and the total must not cover more than 50% of the curtilage. Tighter rules apply in conservation areas and national scenic areas, so check with your local council before you start.

Northern Ireland: similar rights, tighter rules near boundaries

Northern Ireland's permitted development rules closely mirror those in England. A detached outbuilding is generally allowed up to 4 m overall (dual-pitched roof) or 3 m for other roofs, with a 2.5 m eaves limit, provided it sits to the rear and the outbuildings together cover no more than 50% of the garden around the original house. Within 2 m of a boundary, the whole structure is capped at 2.5 m. The NI Planning Portal is the place to confirm the current limits for your address.

Republic of Ireland: exempted development

In the Republic of Ireland the key concept is exempted development. A shed, garden room or similar structure to the rear of the house is generally exempt from planning permission if the combined floor area of such structures does not exceed 25 m², it does not reduce the remaining private open space below 25 m², and the height stays under 3 m (or 4 m with a tiled or slated pitched roof). It must not be used as a habitable room or for keeping animals. Anything at the front of the house, or above these limits, needs permission from your local authority.

Country comparison at a glance

JurisdictionGoverned byGuide size without permissionTypical boundary rule
England & WalesLocal planning authority≤ 4 m height, ≤ 50% of garden (permitted development)2.5 m height if within 2 m of a boundary
ScotlandLocal council≤ 4 m height, ≤ 50% of curtilage2.5 m height if within 1 m of a boundary
Northern IrelandLocal council≤ 4 m height, ≤ 50% of garden2.5 m height if within 2 m of a boundary
Republic of IrelandLocal authority≤ 25 m² floor area (exempted development)to the rear, behind the building line

The figures in both tables are rules of thumb and deliberately rounded. They are no substitute for reading the current regulations or for a definitive answer from your local authority.

How to stay on the safe side — your checklist

  1. Check your local development plan and any conservation-area or Article 4 designation (online on your council's planning portal, or in person).
  2. Read the current permitted-development or exempted-development rules for your address — especially the size and height limits for your type of structure.
  3. Measure the distance to your neighbour's boundary; if you are building close to the line, tell your neighbour early and, where the Party Wall Act applies, serve notice in writing.
  4. Ask your local planning authority for written confirmation — many offer a pre-application check or a lawful development certificate that puts the position beyond doubt.
  5. Only pour the first footing once you have permission, or written confirmation that the work is permitted development.

The more precisely you know the dimensions, height and footprint in advance, the easier the conversation with your planning officer will be — a clean plan with exact measurements is the best starting point. A tool like HolzBau 3D helps you plan your project to scale and keep the relevant measurements to hand. But the binding answer to the permission question only ever comes from one place: your local planning authority.

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