Permitted Development Guidelines

In most instances building a log cabin/garden room in your garden falls withing the remit of Permitted Development as long as its purpose is incidental to the enjoyment of the dwellinghouse.

For peace of mind it is possible to easily obtain written confirmation whether planning permission is/isn’t required by submitting a ‘Do I need planning?’ form through your local Council Planning Portal.  It is normally submitted with a copy of an ordnance survey map for the property with the location of the garden room marked on it and a supporting e-mail with an outline of the usage and a proposed picture of the Garden room.  A response to this is usually provided within 10 days of submitting this application.

In brief, a garden room is considered to be permitted development (not needing planning permission), if it meets the following requirements and is of ancillary use to the main house:

  1. The building is not built forward of the principal elevation of the main house.
  2. The overall height of the building is less than 2.5 metres if the garden room is within 2 metres of the boundary.
  3. A building situated more than 2 metres away from the boundary with a single pitched roof can have a maximum height of 2.5 metres at the eaves and 3 metres at the ridge. For dual pitched roofs more than 2 metres away from the boundary the building may have a maximum height of 2.5 metres at the eaves and 4 metres at the ridge.
  4. The building is single storey and does not have a veranda, balcony or raised platform. (Decking of less than 300mm high is acceptable.)
  5. No more than half the area of land around the “original house”* is covered by additions or other buildings.
  6. In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites the maximum area to be covered by buildings that are more than 20 metres from house is limited to 10 square metres.
  7. The garden building is not to the side of a dwelling located within designated land*.
  8. The garden building is not within the curtilage of listed building.
  9. To be permitted development any new building must not itself be separate, self-contained, living accommodation and must not have a microwave antennae.
  10. The garden building does not exceed 30 square metres in area.

*The term “original house” means the house as it was first built or as it stood on 1 July 1948 (if it was built before that date). Although you may not have built an extension to the house, a previous owner may have done so.

*Designated land includes national parks and the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites.

Building Regulations

  1. For Garden Buildings, building regulations will not normally apply if the floor area of the building is less than 15 square metres and contains no sleeping accommodation.
  2. If the floor area of the building is between 15 and 30 square metres you will not normally need building regulation approval providing that the building contains no sleeping accommodation and is either at least 1 metre from any boundary or it is constructed of substantially non-combustible materials.