Extensions - proposed regime

Please bear in mind that this is a guide to the proposed changes to the planning system. The limits and restrictions outlined here will not apply until the law is changed. The changes will not affect any works started before that date. Building Regulations guidance can be found elsewhere on the Portal.

For current guidance on the planning and building regulations regime see 'Extensions' in our Common Projects section.

The Government intends to introduce the following limits for extensions that will be allowed without the need for specific planning permission:

• No extension forward of the principal elevation or side elevation facing onto and visible from a highway. 'Principal elevation' will in almost all cases be the front of the house.
• Maximum depth of a single-storey rear extension of three metres for an attached house and four metres for a detached house.
• Maximum depth of a rear extension of more than one storey of three metres including ground floor.
• In designated areas no permitted development for rear extensions of
  more than one storey.
• Maximum eaves height of extension three metres within two metres of boundary.
• 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 or existing rear wall if closer than seven metres to boundary.
• Roof pitch of extensions higher than one storey to match existing house.
• Side-facing windows above one storey to be obscure-glazed; top opening allowed.
• Materials to match existing house.
• No raised terraces, verandas or balconies.
• Maximum 50 per cent coverage of garden.
• In designated areas side extensions and cladding will require planning permission.

Please bear in mind that this is a guide to the proposed changes to the planning system. The limits and restrictions outlined here will not apply until the law is changed. The changes will not affect any works started before that date. Building Regulations guidance can be found elsewhere on the Portal.

For current guidance on the planning and building regulations regime see 'Extensions' in our Common Projects section.