Planning permission is not normally required when undertaking a loft conversion in your home. Most conversions can all be completed under permitted development.

However, permission is required where you extend or alter the roof space and it exceeds specified limits and conditions below:

  • The volume exceeds 40 cubic metres for terraced houses.
  • The volume exceeds 50 cubic metres for both detached and semi-detached houses
  • The extension goes beyond the plane of the existing roof slope of the principal elevation that fronts the highway.
  • The extension you are planning is higher than the highest part of the existing roof
  • Your chosen materials are different in appearance to the existing house
  • You are planning verandas, balconies or raised platforms
  • Side-facing windows to be obscure-glazed; any opening to be 1.7m above the floor
  • Your roof extension is being planned in a designated area**
  • The roof enlargement overhangs the outer face of the wall of the original house.