How Do I Get a Building Control Completion Certificate

A building control completion certificate is the final piece of documentation that confirms building work has been checked, meets UK building regulations, and is considered legally compliant. Whether you’ve added an extension, converted a loft, or carried out internal structural changes, this certificate provides official evidence that the work is safe, sound, and signed off.

Obtaining it isn’t automatic. It requires following the correct process from the start of your project and cooperating with building control inspectors throughout the job.

Start With the Right Application

To get a completion certificate, the first step is to make a formal application to building control before any work begins. You can do this through your local authority or an approved private inspector. There are two main routes: a full plans application, which includes detailed drawings and gets checked for compliance in advance, or a building notice, which is simpler and used for smaller domestic jobs.

Whichever route you choose, the approval gives you permission to start the work, but it’s not the end of the process. Inspections still need to take place to monitor what happens on site.

Schedule and Pass Site Inspections

Throughout the build, a building control inspector will visit the site to check progress at key stages. These usually include the foundation work, damp-proofing, drainage installation, structural elements, insulation, and the final finish. Each stage must be signed off before the next one proceeds.

If anything doesn’t meet regulations, the inspector will inform the builder or contractor so it can be corrected. If changes are made that weren’t part of the original plans, they may need to be reviewed and approved separately.

The number of inspections varies depending on the type and complexity of the project, but missing them or carrying out work without checks can delay or even prevent you from receiving a completion certificate.

Notify Building Control at Completion

Once the project is finished, you need to notify building control that the work is complete. They will carry out a final inspection to assess the overall quality and compliance of the finished result. This is a vital step, and it’s your responsibility to ensure the inspector has access and that the work is ready for review.

If the final inspection is successful, the inspector will confirm that all aspects of the build meet the required standards and approve the issue of the certificate.

Receive the Completion Certificate

After final approval, a completion certificate is issued. This confirms that the work complies with current building regulations and has been properly inspected. It’s an important legal document that you should keep safe.

You may need it when selling the property, arranging insurance, or resolving disputes. If work was carried out by a Competent Person under a self-certification scheme, you may receive a compliance certificate from the installer instead, but for most structural work, the building control body issues the official completion certificate.

What if You Don’t Have a Certificate

If the work is already complete but no certificate was issued, you may need to apply for a regularisation certificate. This involves a retrospective inspection to check whether the finished work complies with regulations. In some cases, you may be required to uncover parts of the work to allow the inspector to assess it properly.

This process can be time-consuming, more expensive, and more uncertain than getting approval from the start. It’s always better to follow the proper procedure and secure your certificate as the work progresses.

What Can Delay a Completion Certificate?

The most common reason for delays is missed or incomplete inspections. If a builder skips a key inspection stage — such as foundations, drainage, or insulation — the inspector may not be able to verify compliance later, and this can prevent the certificate from being issued.

Changes to the original plans without notifying building control can also cause problems. Even small deviations might need to be reassessed. If the inspector is unaware of changes or hasn’t approved them, they may refuse to issue a certificate until the work is brought back in line or new drawings are submitted.

Unfinished work is another barrier. This includes small things like missing skirting boards, incomplete fire safety features, or poor-quality finishes. The inspector needs to see a finished product that clearly meets the building regulations, so the job must be fully completed before the final sign-off.

Who Actually Applies for the Certificate?

The application and inspection process usually starts with the property owner or developer. However, in many domestic projects, especially extensions or renovations, the builder or contractor handles the communication with building control and arranges the inspections.

That said, it’s ultimately the homeowner's responsibility to ensure that a certificate is issued. If a builder finishes the job and moves on, and no final inspection was booked, the owner could be left chasing paperwork or paying for further inspections to get the job signed off

Can You Get a Certificate Years Later?

If no certificate was issued at the time of the work, you can apply for what's known as a regularisation certificate. This is only available for work completed after 11 November 1985. The process involves a detailed inspection, and parts of the work may need to be exposed or redone so the inspector can check compliance.

There's no guarantee that a regularisation certificate will be issued. If the work doesn't meet current standards or cannot be safely assessed, you may be required to bring it up to code — which could involve costly remedial work. This is why it's better to get a proper completion certificate during the project, not after the fact.

Digital Access to Certificates

Many local authorities and private inspectors now issue digital completion certificates. These can often be accessed via an online portal or emailed as a PDF. It's a good idea to keep both a digital and hard copy on file.

Some councils also offer historical search services, where you can request copies of old certificates linked to a property. These are useful during house sales or disputes over whether work was approved.

How Completion Certificates Help in the Future

A valid certificate makes selling your home smoother. Solicitors and surveyors often ask for it as part of the conveyancing process. It also helps during property insurance claims, as insurers may request proof that building work was compliant and properly signed off.

If there’s ever a structural issue, or if a neighbour raises a concern about the impact of your work, the completion certificate shows that the project followed the correct process and was approved by a qualified inspector.

Final Word

Getting a building control completion certificate is the final confirmation that your project meets the standards set by UK law. It protects you, adds value to your property, and proves that the work was done correctly. From the first application to the final inspection, staying on top of the process is essential. If you're planning building work, make the certificate part of your checklist from the beginning — because without it, your project isn’t truly complete.