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.
• Maximum height of a single-storey rear extension of four metres.
• Maximum depth of a rear extension of more than one storey of three metres beyond the rear wall of the 'original house'* including ground floor.
• 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.

Please note: the permitted development allowances described here apply to houses not flats, maisonettes or other buildings.

Under new regulations that came into effect from 1 October 2008 a loft conversion for your house is considered to be permitted development, not requiring an application for planning permission, subject to the following limits and conditions:

• A volume allowance of 40 cubic metres additional roof space for terraced houses*

• A volume allowance of 50 cubic metres additional roof space for detached and semi-detached houses*

• No extension beyond the plane of the existing roof slope of the principal elevation that fronts the highway

• No extension to be higher than the highest part of the roof

• Materials to be similar in appearance to the existing house

• No verandas, balconies or raised platforms

• Side-facing windows to be obscure-glazed; any opening to be 1.7m above the floor

• Roof extensions not to be permitted development in designated areas**

• Roof extensions, apart from hip to gable ones, to be set back, as far as practicable, at least 20cm from the eaves

*Bear in mind that any previous roof space additions must be included within the volume allowances listed above. Although you may not have created additional space a previous owner may have done so.

**Designated areas include national parks and the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites.

Please note: the permitted development allowances described here apply to houses not flats, maisonettes or other buildings.