PLANNING PERMISSION

Garden rooms are classed as outbuildings, which are considered a permitted development. This means  planning permission for garden rooms is not usually required before they are built. However, this is only as long as they meet the following criteria:

Planning permission for garden rooms:

  • A garden room cannot be built on any land forward of a wall forming the principal elevation.
  • The garden room must be single-storey with a maximum eaves height of 2.5 metres and a maximum overall height of four metres if it has a dual-pitched roof. The maximum height for any other type of roof should be 3 metres.
  • If within two metres of the boundary of the curtilage of the dwelling or house, the maximum height must be 2.5 metres.
  • There must be no verandas, balconies or raised platforms present.
  • Additions or other buildings would cover no more than half the land area around the original house. The term ‘original house’ refers to the house as it was first built or stood on 1 July 1948 (if it was built before that date).

However, suppose you live in a National Park, the Broads, an Area of Outstanding Natural Beauty (AONB), a World Heritage Site, a conservation area or in a listed building. In that case, there are other criteria that you need to be aware of:

  • In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites, the maximum area to be covered by a garden room over 20 metres from the house must be 10 square metres.
  • If living in any of the areas mentioned in the previous point or a conservation area, garden rooms built at the side of the property will require planning permission.
  • For listed buildings, any garden room built within its curtilage will require planning permission.

Flats, Maisonettes and other considerations

It’s also essential to remember that the guidance above only applies to houses. Rules for attaining planning permission are different for flats and maisonettes. Planning permission will likely be required for these property types, so check with your local planning authority before any work begins. 

Converted houses

The previously covered guidance doesn’t apply to converted houses or houses created through the permitted development rights to change use. Information regarding the change of use is available here. Additionally, this guidance also doesn’t cover other buildings.