This guidance reflects temporary increases to the size limits for single-storey rear extensions that must be completed by 30 May 2019, and the associated neighbour consultation scheme.
An extension or addition to your house is considered to be permitted development, not requiring an application for planning permission, subject to the following limits and conditions:
- No more than half the area of land around the “original house”* would be covered by additions or other buildings.
- No extension forward of the principal elevation or side elevation fronting a highway.
- No extension to be higher than the highest part of the roof.
- Single-storey rear extension must not extend beyond the rear wall of the original house* by more than three metres if an attached house or by four metres if a detached house.
- In addition, outside Article 2(3) designated land* and Sites of Special Scientific Interest the limit is increased to 6m if an attached house and 8m if a detached house until 30 May 2019.
- These increased limits (between 3m and 6m and between 4m and 8m respectively) are subject to the prior notification of the proposal to the Local Planning Authority and the implementation of a neighbour consultation scheme. If objections are received, the proposal might not be allowed.
- Maximum height of a single-storey rear extension of four metres.
- Extensions of more than one storey must not extend beyond the rear wall of the original house* by more than three metres.
- Maximum eaves height of an extension within two metres of the boundary of three metres.
- Maximum eaves and ridge height of extension no higher than existing house.
- Side extensions to be single storey with maximum height of four metres and width no more than half that of the original house.
- Two-storey extensions no closer than seven metres to rear boundary.
- Roof pitch of extensions higher than one storey to match existing house.
- Materials to be similar in appearance to the existing house.
- No verandas, balconies or raised platforms.
- Upper-floor, side-facing windows to be obscure-glazed; any opening to be 1.7m above the floor.
- On designated land* no permitted development for rear extensions of more than one storey.
- On designated land no cladding of the exterior.
- On designated land no side extensions.
* The term “original house” means the house as it was first built or as it stood on 1 July 1948 (if it was built before that date). Although you may not have built an extension to the house, a previous owner may have done so.
* Designated land includes conservation areas, national parks and the Broads, Areas of Outstanding Natural Beauty, and World Heritage Sites.
Please note: The permitted development allowances described here apply to houses and not to:
- Flats and maisonettes (view our guidance on flats and maisonettes)
- Converted houses or houses created through the permitted development rights to change use (as detailed in our change of use section)
- Other buildings
- Areas where there may be a planning condition, Article 4 Direction or other restriction that limits permitted development rights.
Installation, alteration or replacement of a chimney, flue or soil and vent pipe: Read guidance on the permitted development regime under Class G of the regime.
Please be aware that if your development is over 100 square metres, it may be liable for a charge under the Community Infrastructure Levy.
Permitted Development for householders – Technical Guidance
You are strongly advised to read a technical guidance document produced by the Government to help understand how permitted development rules might apply to your circumstances. However if you wish to discuss your project needs for permitted development and Building Control contact Architects Atelier Ltd.
Approximately 3 years ago we purchased a rather run down bungalow on a good site with excellent views over the neighbouring countryside. We had a reasonable but limited budget for the improvement works we wanted to undertake. We also had a rough idea of what we wanted to achieve but were unsure of what steps we needed to take to get there. We selected Barry of Architects Atelier to help us realise our plans because he was approachable, reasonable and professional. He explained the process of planning, tendering and project managing the build. We elected to employ him for all three aspects of our build and his help was essential in bringing our build to a satisfactory conclusion particularly when the builder ran into difficulties with deadlines and scheduling of the works. He took time to discuss the various options available, introduced aspects of the build that we as laypeople would never have considered either feasible or affordable such as the provision of shadow gap lighting, appropriate protection against solar gain and a vaulted ceiling. He also helped us negotiate a very good deal with the builder for the works to be undertaken and on a practical level helped us source what we would describe as, “designer”, lighting, a glass and metal balcony system and log burner at what we considered to be a very competitive cost. He was quite simply brilliant and we would have no hesitation in recommending his services to family, friends or the public at large.
Jon & Angela Thompson, Ashley Law