What are the Permitted Development Rules on Garden Rooms?

Rules governing outbuildings apply to sheds, playhouses, greenhouses and garages as well as other ancillary garden buildings such as swimming pools, ponds, sauna cabins, kennels, enclosures (including tennis courts) and many other kinds of structure for a purpose incidental to the enjoyment of the dwellinghouse.

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If you are unsure if your planned building falls into the category of ‘outbuildings’ or if you are unsure if planning permission is required, please contact your local planning authority.

Other rules relate to the installation of a satellite dish, the erection of a new dwelling or the erection or provision of fuel storage tanks.

Outbuildings are considered to be permitted development, not needing planning permission, subject to the following limits and conditions:

• No outbuilding on land forward of a wall forming the principal elevation.
• Outbuildings and garages to be single storey with maximum eaves height of 2.5 metres and maximum overall height of four metres with a dual pitched roof or three metres for any other roof.
• Maximum height of 2.5 metres in the case of a building, enclosure or container within two metres of a boundary of the curtilage of the dwellinghouse.
• No verandas, balconies or raised platforms (a platform must not exceed 0.3 metres in height)
• No more than half the area of land around the “original house”* would be covered by additions or other buildings.
• In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites the maximum area to be covered by buildings, enclosures, containers and pools more than 20 metres from the house to be limited to 10 square metres.
• On designated land* buildings, enclosures, containers and pools at the side of properties will require planning permission.
• Within the curtilage of listed buildings any outbuilding will require planning permission.

*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.

Please note: The permitted development allowances described here apply to houses and not to:

• Flats and maisonettes (view our guidance on flats and maisonettes)
• Converted houses or houses created through the permitted development rights to change use (as detailed in our change of use section)
• Other buildings
• Areas where there may be a planning condition, Article 4 Direction or other restriction that limits permitted development rights.

Information provided via www.planningportal.co.uk