buying

Permitted development rights: what you can build without planning permission

Permitted development rights explained for houses in England: extension, loft and outbuilding limits, and when Article 4 or flats remove them.

4 min read
Last reviewed 4 November 2026
By Your Property Check team

Part 1 of 8

What permitted development means

General information, not advice. The Planning Portal says permitted development rights are a general planning permission granted by Government, not by your local authority. Most carry conditions, and some need prior approval from the local planning authority. Permitted development is separate from building regulations and, where it applies, the Party Wall etc. Act. Everything below is for houses in England, as read on the Planning Portal on 4 November 2026. Rules in Wales, Scotland and Northern Ireland differ.

Part 2 of 8

The main limits for houses

Work	Usually allowed?	Key limit	When it does not apply
Single-storey rear extension	Yes, within limits	Up to 3 m beyond the original rear wall, or 4 m for a detached house; maximum height 4 m	Larger sizes need prior approval; flats are excluded
Single-storey rear extension with prior approval	Yes, if approved	Up to 6 m, or 8 m for a detached house	Not available on Article 2(3) land or an SSSI
Side extension	Yes, within limits	Single storey, up to 4 m high, no wider than half the original house	All side extensions need permission on Article 2(3) land
Extension of more than one storey	Yes, within limits	Not more than 3 m beyond the original rear wall, nor within 7 m of the rear boundary	Side extensions of more than one storey always need permission
Loft conversion	Yes, within limits	Added volume up to 40 cubic metres for terraced houses, 50 otherwise	Flats, and Article 2(3) land
Outbuilding	Yes, within limits	Single storey, eaves up to 2.5 m, height up to 4 m with a dual-pitched roof or 3 m otherwise	Listed building curtilage needs permission

Part 3 of 8

Rules that apply to all extensions

The Planning Portal lists several limits that apply across extensions:

Extensions and other buildings together can cover no more than half the land around the original house.
Height cannot exceed the highest part of the existing roof, and eaves cannot be higher than the existing eaves.
Within 2 m of a boundary, eaves must not exceed 3 m.
No extension in front of the principal elevation, or the side elevation where it faces a highway.
No verandas, balconies or raised platforms, and no alteration to the existing roof.
Exterior materials must look similar to the existing house.

The Planning Portal defines the "original house" as the house as first built, or as it stood on 1 July 1948 if built before that date. Earlier extensions count against the limits.

Part 4 of 8

Loft conversions

For loft conversions the volume figure includes any earlier enlargement. The enlargement must not exceed the height of the existing roof and, on the side facing a highway, must not go beyond the existing roof slope. Side-facing windows must be obscure-glazed, and any opening part must be at least 1.7 m above the floor. The original eaves must be kept or reinstated, with the enlargement set back at least 20 cm from them where practicable.

Part 5 of 8

Outbuildings

No outbuilding is allowed in front of the wall forming the principal elevation. Within 2 m of a boundary, the maximum height is 2.5 m. Platforms must not exceed 0.3 m in height, and the 50 percent land coverage rule applies. In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites, buildings more than 20 m from the house are limited to 10 square metres in total.

Part 6 of 8

What takes rights away

Flats and maisonettes. The Planning Portal says householder rights for many house projects do not apply to flats, maisonettes or other buildings. Houses or flats created under permitted development usually cannot later use householder rights for further work such as an extension.
Article 2(3) land. This includes conservation areas, National Parks, Areas of Outstanding Natural Beauty, the Broads and World Heritage Sites. Rights there are more restricted, for example no exterior cladding on extensions.
Article 4 directions. The local planning authority can withdraw rights by issuing a direction, most commonly in conservation areas. Once one applies, work that normally needs no application may need planning permission.
Listed buildings. They have different requirements, and any outbuilding in the curtilage needs permission.

Part 7 of 8

Why buyers and sellers care

If a seller added an extension or conversion, the buyer's solicitor will usually ask whether it was permitted development or had permission, and whether building regulations sign-off exists. A permitted development extension is not exempt from building regulations. Check the property's history with our guide to the checks to run before buying a house, and look up past applications with the planning applications tool. Covenants can also restrict building even where planning does not, as explained in our restrictive covenants guide.

Part 8 of 8

Check before you build

The Planning Portal advises contacting your local planning authority before work starts. They can confirm whether the work is permitted and whether any part needs an application, including whether an Article 4 direction applies. Do not rely on a summary like this for a project.

This page is general information, not advice.

Our take

Check the limits, then ask the council

Our view: permitted development is generous but conditional. The usual mistakes are forgetting that earlier extensions count against the limits, assuming flats have the same rights as houses, and missing an Article 4 direction. It matters at sale too, because a buyer's solicitor will ask whether past work was permitted or had permission.

Our planning applications tool is a place to start looking at planning around an address, and OfferCheck includes planning in its plain-English risk report on any UK address, with every figure sourced.

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Our opinion, drawn from the facts on this page: not advice and not a forecast. We earn from OfferCheck reports and from introducing sellers to cash buyers, so weigh it with that in mind (see our disclosure). We are not authorised or regulated by the FCA.

Questions, answered

Frequently asked questions

What are permitted development rights?

The Planning Portal says they are a general planning permission granted by Government that lets you carry out certain building work without a planning application, subject to conditions and size limits.

How big can a single-storey rear extension be under permitted development?

On the Planning Portal, up to 3 m beyond the original rear wall, or 4 m for a detached house, with a maximum height of 4 m. With prior approval, up to 6 m, or 8 m for a detached house.

Do permitted development rights apply to flats?

No. The Planning Portal says householder rights for many house projects do not apply to flats, maisonettes or other buildings, so those usually need a planning application.

What is an Article 4 direction?

It is a direction by the local planning authority that withdraws permitted development rights in an area, most commonly a conservation area. Work that would normally need no application may then need planning permission.

Do I still need building regulations approval?

Permitted development removes the need for a planning application only. The Planning Portal treats building regulations as a separate matter, so check with building control.

Where this comes from

Sources

Last reviewed 4 November 2026 by the Your Property Check team. This page is general information, not legal, tax or financial advice. For your own situation, speak to a conveyancing solicitor or another qualified professional.