How Not to Lose Your Planning Permission

1st May 2018

Planning permission normally lasts for three years and after those three years, the permission expires. If you had not implemented the permission already, you would need to re-apply after the end of three years. Depending on your particular circumstances, it might be worth implementing the scheme before the end of three years, even if you do not think you will carry on straight away. ­­

There could be many different reasons to not complete development – whether you intend to sell the site with the benefit of planning permission, or the scheme is not financially viable at present, or the winter months make construction difficult. Whatever the reason, is it is important to start work before the end of the expiry date if you do not want to lose your planning permission.

What it takes to start development will vary depending on the description and scale of development. You will also need to pay attention to any conditions on the planning permission that require further details to be approved before development starts.

We have advised clients on a couple of recent sites in London in this situation. One site in the London Borough of Hillingdon in High Street, Uxbridge had planning permission for five residential units. The client wanted to protect the planning permission without demolishing the existing building. The planning permission was implemented by the construction of a single parking space on part of the site outside the footprint of the existing building.

In the Royal Borough of Kensington and Chelsea, a client had purchased a house with planning permission for a basement and various other alterations including blocking up a window in the existing conservatory. They were not ready to commence the basement works but wanted to protect the consent that would not now be granted due to a change in planning policy. We advised them to implement the consent by blocking up the window in the conservatory, which could be done without disturbing the rest of the property.

Whichever way you intend to start developing it is also helpful, and sometimes essential, to secure a ‘certificate of lawful development’ from the relevant Council. We successfully did this in both examples above. This certificate is a legal document that confirms that the development has lawfully started and that the rest of the development can continue after the expiry of three years. This is important if you were to sell the site and the new owner wants the reassurance that the approved development can be completed.

It is important to remember that applications for a certificate of lawful development need to be made before the end of three years and good evidence is required to demonstrate the work has started.

It is also useful to be aware that you can request a longer expiry date, sometimes of up to five years on your planning permission. You will need to have a good reason to request this, but that is worth considering in advance.

Bell Cornwell would be pleased to review what is needed to start your development, whether a certificate is needed, and what evidence you should have to support the application. We have been very successful with applications for certificates for the commencement of development.

For more information please contact us at: 020 3960 1530 or

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