Depending on whether you’re planning to improve your existing house or carry out significant works to the one you intend to buy, it pays to understand the scope of the available permitted development rights.

Permitted development rights are there to allow householders to improve and extend their homes without applying for planning permission.

They are typically granted as General Development Planning Orders (GDPOs), which apply separately to EnglandWalesScotland and Northern Ireland. They provide implied planning consent to carry out certain classes of development in your home.

To carry out any work under permitted development, it must strictly conform to the current criteria. Before undertaking any work, we recommend checking with your local authority before starting or confirming with a qualified surveyor that they are in correct order.

It’s worth checking with your local authority as more and more are beginning to offer a consultancy service, with a small fee charged, and they will then confirm in writing whether or not a planning application is required.

Even though your loft conversion will be considered permitted development it will still be subject to limits and conditions as follows:

  • It must not exceed the volume allowance of 40 cubic metres for terraced houses
  • It must not exceed the volume allowance of 50 cubic metres for both detached and semi-detached houses
  • Any proposed extension beyond the plane of the existing roof slope of the principal elevation that fronts the highway is NOT considered permitted development.
  • No part of the extension to be higher than the highest part of the existing roof
  • All materials should be similar in appearance to the existing house
  • Any verandas, balconies or raised platforms are considered NOT to be classed as permitted development.
  • Any side-facing windows should be glazed with obscure glass and non-opening with any opening parts to be 1.7m above the floor.
  • Roof extensions are considered not to be classed as permitted development in designated areas
  • Roof extensions, apart from hip to gable ones, should be set back from the original eaves at least 20cm.
  • Any roof enlargement cannot overhang the outer face of the wall of the original house.



The permitted development allowances described here only apply to house, they do not apply to the following:

  • Flats and maisonettes 
  • Converted houses or houses that have already been created through the permitted development rights to change of use 
  • Areas where there may be an existing planning condition