Lawful Development Certificates in London

A lawful development certificate (LDC) is a formal confirmation from the local authority. A certificate of proposed use or development confirms that works you intend to carry out would be lawful as permitted development; a certificate of existing use or development confirms that works already carried out are lawful. Unlike planning permission, an LDC is a legal determination of lawfulness, not a judgement on the merits of a design.

Even where you are confident works are permitted development, a certificate removes doubt — for you, for neighbours, and crucially for a future buyer’s solicitor or a lender. It can also regularise older works whose status is unclear. We assess whether a certificate is appropriate, prepare the precise drawings and evidence an LDC requires, and manage the application.

There are two LDCs and they work differently. A certificate of lawful proposed use or development confirms, before you build, that the works you intend would be lawful — typically as permitted development. A certificate of lawful existing use or development confirms that something already built or in use is lawful, often because it has become immune from enforcement. In both, the burden of proof sits with the applicant, and the council decides on fact and law rather than on the design’s merits, so the case has to be made precisely.

Works carried out without permission are not automatically unlawful forever: they can become immune from enforcement once they have been in place long enough, with the relevant period depending on the type of breach and when it occurred. An existing-use certificate is how that immunity is formally established — but it stands or falls on evidence, such as dated photographs, invoices, statutory declarations, council-tax records and utility bills proving when the works were done. We assess whether the immunity case is realistic and assemble the evidence to support it.

Because an LDC is a determination of fact and law, it is won or lost on accuracy, not persuasion. The drawings must show exactly what is proposed or exists, the application must cite the precise permitted development class and demonstrate compliance with each of its conditions, and any evidence must be unambiguous. Applications fail on technicalities — a measurement over a limit, a missing condition, weak evidence — far more often than on substance. We prepare these to the standard the determination demands, so the certainty you are seeking is actually delivered.