Before they ask:
Missing building regulations certificate — should I ring the council?
Usually no — not before you have spoken to your conveyancer. Indemnity insurers require that neither side has raised the irregularity with the local authority, so asking can remove an option worth five figures for a £30–£50 policy.
- How long
- 2–6 weeks for council records
- Typical cost
- Policy typically £30–£300
- Who asks
- Buyer's solicitor
This is the single most expensive piece of well-meant helpfulness in a house sale, and almost nobody is warned about it.
What happens
Somewhere in your house there is work with no Building Regulations completion certificate. A loft conversion. An extension. A knocked-through wall. Perhaps you did it; perhaps it was there when you bought.
At some point in the sale, the buyer’s solicitor asks for the certificate. You cannot find it. The obvious, sensible, responsible next step is to ring the council and ask whether they have a record.
That call can cost you thousands.
Why
Where sign-off is missing, one common route is an indemnity insurance policy. It does not make the work compliant. It covers the financial consequences if the local authority ever takes enforcement action. Policies are cheap — often somewhere between £30 and a few hundred pounds depending on the property value and the nature of the work — and they are routine enough that solicitors handle them all the time.
The catch is in the underwriting. Insurers generally require that neither party has contacted the local authority about the irregularity, and policies commonly exclude claims where the insured party started that conversation.
The trap. A £35 policy covering five figures of exposure disappears because you were trying to be helpful. Because the policy is normally arranged by the buyer’s solicitor near exchange, you never see the mechanism that just closed the option.
What to do instead
- Stop. Do not contact the council, the planning department or building control about it.
- Look through your own paperwork first. Completion certificates often surface in the bundle from when you bought, in a file from the builder, or with your own conveyancer’s archive from the purchase.
- Tell your conveyancer what you have and have not found, and say explicitly that you have not approached the council.
- Let them advise on the route. Indemnity insurance, regularisation, or doing nothing are all possibilities, and which applies depends on the work, its age, and what the buyer’s lender will accept.
The options, roughly
| Route | What it is | Rough cost | Rough time |
|---|---|---|---|
| Indemnity insurance | Covers enforcement risk, does not make the work compliant | £30–£300 | Days |
| Regularisation certificate | Building control inspects and certifies the existing work | Council fee plus any remedial work | Weeks to months |
| Do nothing | Disclose and let the buyer decide | Nil | Immediate, but may cost you in negotiation |
Which of these is right is not a decision to make from a web page. It depends on the work, the lender, and what the buyer will wear — which is what your conveyancer is for.
The thing to take away
If you know there is work in your house without paperwork, the time to find out is now, months before anyone asks. Not because you can fix it yourself, but because the one action your instincts will push you towards is the one that removes your cheapest option.
Common questions
Does contacting the council really invalidate indemnity insurance?
Indemnity policies for missing building regulations sign-off are typically written on the basis that no approach has been made to the local authority about the issue. Policies commonly exclude claims where the insured party initiated that contact. Wording varies between insurers, which is exactly why the question should go to your conveyancer before you pick up the phone.
Who normally arranges the policy?
Usually the buyer's solicitor, close to exchange, and often at the seller's expense as part of the negotiation. Because it happens late and on the other side of the transaction, most sellers never see the mechanism at all.
What if the work was done a long time ago?
Local authorities have a limited window to require alterations to unauthorised work, and after a long period the practical risk changes. That does not make the enquiry go away, and whether it affects your position is a legal question for your conveyancer rather than something to judge from a web page.
Can I get a certificate retrospectively?
A regularisation certificate is sometimes possible, where building control inspects the work now and certifies it. It can mean opening up finished work, and it is slower and more expensive than indemnity insurance. It is one of the options to put in front of your conveyancer.
Last reviewed 13 September 2026. England and Wales.
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