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Lawful development certificates for planned or existing work

A large certificate with a gold seal and a lawful stamp beside a dated calendar card and a house with its extension ticked

For owners who want certainty that planned work is permitted development, or that existing work or a use is now lawful. Compare quotes from professionals who can build the evidence and apply.

A lawful development certificate is a legal decision from your council confirming that a proposed project, or an existing building, use or activity, is lawful in planning terms. A certificate for proposed work is often used to confirm that an extension or loft conversion falls within permitted development before building starts. A certificate for existing work can show that it has become immune from enforcement because time limits have passed, or that it never needed permission. Unlike a planning application, it is decided on facts and law rather than planning merit, so a good professional concentrates on precise drawings, the exact wording of the rules and solid evidence.

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Certificates of lawfulness across the UK

Questions people ask

Do I need a lawful development certificate for permitted development?

It isn’t compulsory, but it’s often sensible. Permitted development rules are detailed, and a small misreading can mean the work needs planning permission after all. A certificate for proposed work gives you written confirmation before you build, which buyers, lenders and their solicitors often ask to see when you sell.

What evidence do I need for an existing use or building?

Enough to show, on the balance of probabilities, that the work or use has continued for the relevant period without a significant break, or that it never needed permission. Useful evidence includes dated photos, aerial images, invoices, council tax and utility bills, tenancy agreements and sworn statements from people with direct knowledge. Precise, consistent evidence carries more weight than general recollections.

Is a certificate the same as planning permission?

No. A certificate confirms that something is already lawful, or would be if built as shown. Planning permission grants consent for something that otherwise wouldn’t be allowed. The council can’t attach conditions to a certificate or refuse it because it dislikes the design, but it will refuse if the facts or evidence don’t support it.

Can neighbours object to a lawful development certificate?

Councils usually don’t have to consult neighbours on these applications, although some publish them and may take account of factual information people send in. Views about whether the work is welcome aren’t relevant, because the decision is about lawfulness, not merit.

What if my certificate application is refused?

The decision explains why. Often it’s because the evidence doesn’t cover the full period, or the design breaks a permitted development limit. You can submit more evidence in a new application, amend the design, appeal, or apply for planning permission instead. Your professional can say which makes most sense.

Available across the UK

Professionals cover the whole of the UK: England, Scotland, Wales and Northern Ireland. Planning and Building Regulations differ between the four nations, and your professional will work to the rules that apply where your property is.