Smaller extensions
If you do not live in a conservation area or a listed building, you may be able to construct a single-storey rear extension without planning permission. This can only be to a depth of:
- 3m to 6m for a semi-detached or terraced house
- 4m to 8m for a detached house
Even if you do not need planning permission, you still need to let us know about your extension. You need to complete the notification of a proposed larger home extension form .
Larger extensions
If your proposed extension is bigger, we will consider it if:
- it is subordinate – this means it is smaller in height, width and depth than the original building
- it avoids blocking sunlight to neighbouring properties
- windows of the extension avoid looking into habitable rooms of neighbouring properties
- it avoids reducing gardens to an unreasonably small size
- it avoids impacting trees on the property or adjacent properties
Planning permission might not be granted if your extension is generally not in line with this advice.