Planning permission is required unless the “Permitted Development (PD)” restrictions are not adhered to. Flats and maisonettes are excluded from PD requirements, planning is always required for them.

Since May 2013 the government extended Permitted development rights and home extensions became easier to build. Below is a summary guide to these extended rights.

These are however difficult to understand as we can take you through the “Certificate of lawful development” process so your works are a legally legitimate development.

This information below 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 home is permitted development, not requiring an application for planning permission from your local planning department, subject to the following limits and conditions:

  • No more than half the area of land around the “original house” would be covered by additions, extensions or other buildings.
  • No extension forward of the principal elevation or side elevation fronting a highway is allowed
  • No extension to be higher than the highest part of the existing 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 (eg. a semi) 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 must not exceed four metres.
  • Extensions of more than one storey must not extend beyond the rear wall of the original home 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 home.
  • 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.

*Designated land is that where the property is in a conservation area or is listed, or the areas is denoted as being “An area of outstanding natural beauty” or a “World heritage site”

For Double Storeys & Side Extensions

Permitted development for double-storey and side extensions can be summarized as below

This guidance reflects temporary increases to the size limits for single-storey rear extensions that must be completed by 30th May 2019, and the associated neighbour consultation scheme.

  • No more than 50% the area of land around the “original house” would be covered by additions or other buildings.
  • No extensions built forward of the principal elevation or side elevation fronting a road.
  • No extension to be higher than the highest part of the roof ridge.
  • Single-storey rear extension must not extend beyond the rear wall of the original house by more than 3m if an attached house or by 4m 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 the 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 the extension within 2m 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 should be no closer than 7m to the rear boundary.
  • Roof pitch of extensions higher than one storey to match existing house materials.
  • Materials to be used must 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.