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Do I need planning permission?

Planning Permission

Planning permission is only required when development occurs (Town & Country Planning Act 1990). As a general guide, you need planning permission for new buildings, major alterations to existing buildings and to change the use of buildings or land.

If you live in a house or bungalow (not a flat) you may be able to alter, extend or improve your property in a variety of ways without needing to make a planning application. This is because houses and bungalows usually have "Permitted Development" rights.

In some instances permitted development rights are removed by a planning condition or an Article 4 direction. It is important that you find out whether your property is affected by carrying out a permitted development constraints check.

Having found out what restrictions there are on your property, you can then use the Planning Portal's guidance to find out more about your proposal:

  • Interactive Guides - Explore the interactive house, terrace or mini guides for popular household building projects including conservatories, extensions, loft conversions, outbuildings and porches.
  • Common Projects - In this section you will find planning and building regulations guidance for many common building work projects for the home.

Larger Home Extension

A homeowner wishing to build a larger single storey rear extension:

  • greater than four metres and up to eight metres for a detached house or 
  • greater than three metres and up to six metres for any other type of house

must notify and gain approval from the Local Planning Authority prior to development starting, by completing and submitting the Notification of a Proposed Larger Home Extension form. It is not possible to undertake this process retrospectively.

Works / Uses Not Requiring Planning Permission

Some works / uses are not classed as "development" and therefore do not require planning permission. These can include: -

  • maintenance, improvements or other alterations inside the building;
  • works which do not "materially affect" the way the outside of the building looks;
  • changes of use within the same use class as the existing lawful use;
  • certain uses for agriculture or forestry.


Taking the above information into account, if you consider the works/use does not require planning permission then you can make an application for a "Certificate of Lawfulness".  The information provided with the application is considered and if confirmed, the Authority will issue a legally binding decision.  This gives you certainty that your proposal does not require planning permission.  In addition to the peace of mind it provides, it may be asked for by purchasers if you sell your property.

If planning permission is required, a formal planning application for "Full Planning Permission" will need to be submitted.

You are responsible for establishing the necessary permissions, consents and approvals required. If you start work on property or land without obtaining the correct permission, you could be required to put things back to how they were.

Further information: