What Is a Regularisation Certificate?
A regularisation certificate (also called a regularisation application or retrospective Building Regulations approval) is the process by which building works that were carried out without Building Regulations approval are retrospectively checked and, if they comply, approved.
It is the retrospective equivalent of the Full Plans or Building Notice routes to approval.
When Is a Regularisation Certificate Needed?
Work done without Building Regulations approval becomes an issue most commonly when:
- A property is being sold and the solicitor's searches reveal an absence of Building Regulations completion certificates for works visible from the property (for example, an extension, loft conversion, or internal structural alteration)
- A buyer's surveyor notes works that would normally require Building Regulations approval and no documentation is available
- The current owner discovers that a previous owner carried out significant works without approval
Works that normally require Building Regulations approval include:
- Extensions and loft conversions
- Structural alterations (removing walls, adding steels)
- New bathrooms (drainage)
- New boiler installations
- Electrical work (in some circumstances)
- New stairs
The Regularisation Process
A regularisation application is made to the local authority Building Control department (not to a Registered Building Control Approver — regularisation can only be handled by local authority Building Control for domestic extensions).
The process typically involves:
Application: Submit a regularisation application form with plans of the work as built, details of the work carried out, and a fee (typically 150–200% of the standard Building Regulations fee)
Inspection: The Building Control officer inspects the work. For hidden elements (foundations, structural connections, insulation within walls), opening up may be required to allow inspection
Assessment: The officer assesses whether the works, as built, comply with the Building Regulations current at the time the work was carried out
Certificate: If compliant, a regularisation certificate is issued. If not compliant, remediation work is required before the certificate can be issued
What If the Works Do Not Comply?
If the Building Control officer finds that the works do not comply, remediation is required. This might mean:
- Upgrading insulation levels to meet the standard at the time of the works
- Rectifying structural details
- Adding fire protection to structural elements
- Improving ventilation or drainage
In some cases, the cost of remediation can be significant — particularly where the works have been completed, decorated, and concealed.
Can the Local Authority Enforce Old Unapproved Works?
The local authority has enforcement powers under the Building Act 1984, but they lapse 12 months after the completion of the unauthorised works. After 12 months, the authority cannot require the works to be altered or removed.
However, the absence of a completion certificate remains on the property record and may affect mortgage lending and sale.
Indemnity Insurance as an Alternative
Where regularisation is not possible or practical (for example, works that are over 20 years old and fully concealed), solicitors sometimes use building regulations indemnity insurance as an alternative. This is a one-off insurance policy that protects the buyer and their lender against the cost of any enforcement action by the local authority.
Indemnity insurance is not a regularisation certificate — it does not confirm the works are compliant. It only provides financial protection if a problem arises.
RCB Design & Build
RCB can assist clients in assessing whether unauthorised works on a property are likely to require regularisation, identifying the likely cost of bringing works into compliance, and coordinating the regularisation application with the local authority.