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Your Completion Certificate: Why It Matters and How to Get One

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The building control completion certificate proves your extension complies with building regulations. Without it, selling or remortgaging becomes complicated. Here's how to get one, and what to do if you don't have one.

Beginner£01 hourLead time: 2-4 weeks to receive

Most homeowners assume that once the builder has left and the scaffold has come down, the job is done. The extension is standing. It's plastered and painted. You're living in it. The only thing left is some paperwork.

That paperwork will matter enormously. Not now. The moment you try to sell.

The building control completion certificate is the document that proves your extension was built in compliance with building regulations. Your buyer's solicitor will ask for it as standard practice in conveyancing. Your mortgage lender may require it. Your insurer may need it if you ever make a structural claim. And if it doesn't exist, your options for resolving that range from expensive to very expensive, with an important catch. The two main routes are mutually exclusive once you make a single phone call to the wrong person.

1 day

How long it took for a completion certificate to be issued after the final trade certificates were submitted on a real 55.5m² extension. The BCO had been waiting for over four months. Every day of that delay was caused by outstanding trade certificates, not by the inspection process. Your BCO is not the bottleneck.

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