Rear extensions

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 (pdf, 3 page(s), 467.25 KB).

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.