Planning Permission Regulations for Conservatories


Double Glazing


Triple Glazing



A Rated


Planning Permission

A conservatory is now considered permitted development which means that apart from certain conditions you will not need to apply for planning permission.  As time passes the size limits for single-storey extensions built on the rear of a property have been increased and this article reflects these changes which apply between 30 May 2013 and 30 May 2019, in association with the neighbour consultation scheme.

Your conservatory would not be considered a permitted development if the following apply:

  • Over 50% of the land around the original property* would be covered.
  • The extension on a front or side elevation of the home, or facing a highway.
  • Any part of the extension is taller than the existing roof.
  • The new structure extends the original home by over 3 metres (4 metres for detached properties).

In certain areas, such as designated land or SSSIs (Sites of Special Scientific Interest) this limit is extended to 6m, or 8m for a detached property until May 30th 2019. 

Any increased limits (see above) must be agreed under the neighbour consultation scheme.

In addition to the above, you will not need planning permission for the following:  

  • A single-story extension to the rear of the property that is under 4m in height.
  • Extensions over one storey remain over 3 metres of the rear wall and within 7 metres of a boundary opposite the rear wall, based on the position of the original house*.
  • The height of the eaves on the extension are within 2m of the 3m boundary.
  • The eaves and ridge are no higher than the existing property.
  • Side extensions are single storey, maximum height 4m, maximum width half of the original house.
  • For extensions over one storey the roof pitch  matches the existing house.
  • It does not have a veranda, a balcony or any raised platform

On designated land* you must not build rear extensions higher than one storey, the exterior must not be cladded, side extensions are not permitted.

* “Original house” is a house as it was first constructed if it was built after 1 July 1948, or as it originally stood on that date.  For example, the extension may have already been built by the previous owner.

* Designated land:  This includes all national parks, the Broads and World Heritage Sites.  Also included are any conservation areas and designated AONB (Areas of Outstanding Natural Beauty).


Permitted development allowances relate only to houses and not flats, maisonettes or converted houses developed through a change of use. They also do not relate to other buildings or any area where there is any restriction that limits these permitted developments, eg.  Article 4 direction.

If the property is a listed building you may need to seek consent.

Any development over 100 square meters may face a charge (The Community Infrastructure Levy)

Other technical guidance to view includes the permitted development for householders – a document produced by the Government which will help you to understand how the rules will affect your own particular proposals.