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Certificate of Lawfulness, and the 4 Year Rule

26 October 2017
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Eugene Kim

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Read on to understand the 4 year rule…

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Certificate of Lawfulness of existing use or development,
and the 4 Year Rule


An application for a Lawful Development Certificate is to officialise an unauthorised use or development, and to offset pending council action either to reverse the development or cease the use. These are retrospective applications and can be made via obtaining the form LDC1 from your LPA. If you have done a flat conversion to your house and rented them for over 4 years, you can legalise this development with a Certificate of Lawfulness of existing use or development, as per the 4 Year Rule. We can help you avoid the 4 year rule planning enforcement. Follow the link for your free quote.  

Do I need a Lawful Development Certificate?

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Obtaining a Certificate of Lawfulness of existing use or development is a good move because you can use the fullness of time to apply to continue your use and avoid having to making a retrospective application for planning permission. Also, in the event of a sale or remortgage, you could be asked for it by the other solicitor or lender.


Certificate of Lawful Use and the 10 Year Rule

Would your building qualify?

If you can show a continuous use on non-residential buildings for at least 10 years, or that you have not complied with a condition for that time, or that the build has been complete for just 4 years or had residential use for that time.

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Lawful Development Certificate;
Decision Time

How To Start: Your architect can act as your agent to satisfy the council you have a valid application. They will submit proof of your continuous level of use with various evidence, as relevant to each case, which they will gather from you. This can be quite complex, so it is best to appoint a professional in the interest of success.

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Extension Architecture can create architectural drawings to show existingand proposed, or current and previous layouts


In Short

We have vast experience of submissions, including LDCs. We can prepare your application for a Certificate of Lawfulness of existing use or development. Ring us for a free telephone consultation about the four year rule, the ten year rule, or a certificate of lawful development on 0203 409 4215 or email us your details for a digital quote and a call-back.


  • LDC applications can be current or retrospective
  • The certificates are to show that planning permission is not required
  • They are good for developers, buyers, solicitors and re neighbours’ complaints
  • The lawful development certificate fee is cheaper if you obtain the certificate in advance. Ask for form LDC2 from your LPA.
    For planning application fees 2017 see the planning application fee calculator
  • For Retrospective Certificates it is form LDC1
  • Fill the form with adequate and clear information to avoid delay or refusal
  • Supply original utility bills which can be returned to you if requested
  • Your application will be on the public register so be aware with any sensitive information, though they are not publicised like planning applications
  • No neighbour consent is sought by the LPA
  • Lawful development certificate timescale for applications is within 2 months, unless items are missing
  • When you get your certificate, your use will remain valid if there is no material change
  • Lawful Development Certificate Refused: If you are refused, you can either apply for planning permission or appeal to the Planning Appeals Commission who can overturn the refusal if it did not have a strong basis

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Contact Us

Call us for a free planning consultation & quotation, or use our online contact form. One of our Planning Consultants will call you back to discuss your requirements.

Youno Kim is the Director of EA and has extensive experience in retrospective applications for Lawful Development. His strength is his full grasp of the intricacies within Local Planning Policies and relevant Government legislation. He can easily advise you about the 4 year rule and the best planning route for you, as can our planning team.

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Eugene Kim

Eugene Kim, Founder and Managing Director of Extension Architecture, has led the firm for over 14 years, consistently delivering quality solutions. His dedication has been key to the company's growth and success.

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