Lawful development certificates
A certificate of lawfulness is the formal answer to "can you prove it?" — the question that surfaces during a sale, a remortgage, or a dispute with a council. It confirms that works or a use are lawful, in a document a solicitor will accept.
Plenty of development is entirely lawful without anyone ever applying for anything. Permitted development rights exist precisely so that routine work does not need permission. The difficulty comes later, when somebody asks you to demonstrate it.
The two types
| Existing | Proposed | |
|---|---|---|
| Confirms | Works or a use already carried out are lawful | Something you intend to do would be lawful |
| Relies on | Evidence of what happened and when | Drawings and a clear description |
| Typical trigger | A sale, a remortgage, a council enquiry | Removing doubt before building |
When people actually need one
- Selling. Conveyancing enquiries ask about alterations. "It was permitted development" is often not enough for the buyer's solicitor, and the problem lands mid-transaction.
- Remortgaging or refinancing. Lenders and their valuers ask similar questions, particularly on converted or extended properties.
- Before building. A proposed-use certificate removes the risk of an enforcement argument after the money has been spent.
- After a council enquiry. Where a local authority queries whether something was lawful, a certificate settles it.
- Establishing a use. Frequently relevant for commercial premises where the lawful use matters for a future application, including the two-year condition under Class MA.
The timing problem. Almost nobody gets a certificate when it would be easy. They get one when a buyer's solicitor has already raised it and the chain is waiting. Evidence is easiest to assemble close to the event and hardest a decade later, which is the reverse of when people go looking for it.
Evidence for an existing-use certificate
The burden of proof sits with the applicant, and the case needs to be established on the balance of probabilities. Useful evidence typically includes:
- dated photographs showing the works or the use;
- invoices, receipts and contracts from the build;
- statutory declarations from people with direct knowledge;
- utility bills, council tax or business rates records;
- historical aerial and street-level imagery;
- tenancy agreements or accounts, where a commercial use is being established.
Rarely does one item settle it. A coherent bundle that tells a consistent story usually does.
What we do
- Assess the position. Whether the development or use is in fact lawful, and which certificate applies.
- Identify the evidence. What exists, what is missing, and what can realistically be obtained.
- Prepare the application. The forms, the plans, and a statement setting out the case properly.
- Manage the submission and respond to the council's queries through determination.
Where the honest assessment is that the development was not lawful, we will tell you. There are other routes in that situation, and pursuing a certificate that will be refused is not one of them.
Fixed fees for this service
Quoted in writing before anything starts. No hourly billing.
Basic
Eligibility assessment and written advice.
- Initial eligibility assessment
- Review of your proposed development
- Written planning advice
- Recommended route and next steps
Standard
The application handled end to end.
- Everything needed for the agreed standard submission
- Application preparation
- Submission management
- Council liaison
- Reasonable clarification responses
Premium
Strategic support for complex cases.
- Strategic planning assessment
- Full case management
- Coordination of more complex evidence and support
- Council liaison
- Post-decision guidance
Council application fees and third-party reports or drawings are separate unless expressly included. Complex schemes are quoted bespoke — we will tell you before you commit if your project falls outside the standard packages.
Frequently asked questions
Straight answers to what people actually ask us.
What is a lawful development certificate?
It is a formal determination by the local planning authority that a development or use is lawful. It is not a planning permission and it does not grant anything — it confirms the legal position of something that is already lawful.
There are two types: a certificate of lawfulness of existing use or development, for something already carried out, and a certificate of lawfulness of proposed use or development, for something you intend to do.
Why would I need one if I did not need planning permission?
Because being lawful and being able to prove it are different things. The certificate is documentary evidence that satisfies a buyer, a lender or a solicitor.
The most common trigger is a sale. Conveyancing enquiries ask about works to the property, and an answer along the lines of "it was permitted development" is frequently not enough for the buyer's solicitor. That is when a certificate becomes urgent, and urgent is the worst time to start.
What is the difference between existing and proposed?
An existing-use certificate confirms that works already carried out, or a use already established, are lawful. It relies on evidence of what was done and when.
A proposed-use certificate confirms that something you intend to do would be lawful if carried out as described. It relies on drawings and a description rather than historical evidence, and it is a useful way to remove doubt before spending money on a build.
What evidence do I need for an existing use certificate?
It depends what you are trying to establish, but typically some combination of dated photographs, invoices and receipts, statutory declarations from people with direct knowledge, utility records, council tax or business rates records, and historical aerial imagery.
The burden of proof is on the applicant. The evidence needs to establish the position on the balance of probabilities, so it is worth assembling properly rather than sending in what happens to be on hand.
Can a certificate be refused?
Yes. Refusal usually means the evidence did not establish the case, or that the development was not in fact lawful.
A refusal is not automatically fatal — a further application with better evidence is sometimes possible — but it is much better to get the evidence right first time. A refused application also creates a record that a future buyer's solicitor may see.
How long does it take?
The determination period is generally eight weeks, though straightforward applications are often decided sooner. Assembling the evidence for an existing-use application usually takes longer than the determination itself.
If you are working to a sale timetable, start earlier than feels necessary.
Not sure which route applies to your property?
Send us the address and what you are proposing. We will tell you whether there is a Prior Approval or permitted development route worth pursuing, before you commit to anything.
info@planningservicesonline.co.uk
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