Home Page
About Us
The Design Process
Planning Permission
Building Regulations
Prices
Contact Us

The following information is for guidance only and is not a definitive interpretation of the Planning Act.

Planning permission is required for any domestic extension if any of the following conditions apply:

  • Conditions on the planning permission under which your house was built removed your normal development rights.
  • The cubic content of the proposed extension together with any other previous extensions and outbuildings within 5m of the house would exceed;
1. In the case of the properties in a conservation area, or terraced or end terraced properties: 50 cubic metres or 10% or the original cubic content of the house, whichever the greater, subject to a maximum of 115 cubic metres

2. In the case of semi-detached or detached properties: 70 cubic metres or 15% of the original cubic content of the house, whichever the greater, subject to a maximum of 115 cubic metres
  • The height of the proposed extension would exceed the height of the highest part of the roof of the original house.
  • The height of the proposed extension exceeds 4 metres in height within 2 metres of any boundary.
  • Any part of any extension would be nearer to any highway, which bounds the property, than any part of the original house, unless a distance of 20m from the highway is maintained. (Highway includes public footpath)
  • The area covered by buildings within the site boundary, excluding the original house, will exceed 50% of the total plot area.
  • Your property is a Listed Building.
top of page arrow
W3C valid logo