What Happens If an Extension Was Built Without Building Regulations Approval?
Finding out that an extension was built without Building Regulations approval can be worrying, especially when buying a house or preparing to sell one. However, missing paperwork does not automatically mean that the extension is unsafe or must be demolished.
Blueprint UK
9/14/20262 min read
The important thing is to understand what work was carried out, when it was completed and whether the correct approval was required.
What Is Building Regulations Approval?
Building Regulations approval confirms that construction work meets the required standards for safety, structure, insulation, ventilation, fire protection and other technical matters.
Building Regulations approval is separate from planning permission.
For example:
An extension may have planning permission but no Building Regulations approval.
An extension may not need planning permission because of permitted development rights but may still need Building Regulations approval.
A small conservatory may have been exempt from certain requirements while it remained separated from the house.
What If the Extension Has No Completion Certificate?
If an extension has no completion certificate, the first step is to establish whether Building Regulations approval was ever applied for.
Check:
When the extension was built.
Whether Building Control was involved.
Whether the work was completed by a previous owner.
Whether the local authority has any records.
Whether structural drawings or calculations are available.
Whether the extension was built as shown on the approved plans.
Older properties may have limited records, so it is important not to rely only on the seller’s description.
What If You Are Buying the Property?
If you discover missing Building Regulations paperwork during a house purchase, raise the issue with your solicitor or conveyancer before exchanging contracts.
You may need to ask:
Was Building Regulations approval required?
Was an application made?
Is a completion certificate available?
Can the local authority confirm the records?
Is a regularisation certificate possible?
Would a structural inspection be advisable?
Will the mortgage lender accept the proposed solution?
Do not assume that an extension is automatically approved simply because it has been standing for many years.
Can Retrospective Approval Be Obtained?
In some cases, a regularisation certificate may be available for completed work that did not receive the correct Building Regulations approval.
The local authority may request:
Drawings or technical information.
Structural calculations.
An inspection of the existing work.
Parts of the construction to be opened up.
Remedial work before approval can be issued.
A regularisation certificate is not guaranteed, and the requirements will depend on the age, type and condition of the extension.
Is Indemnity Insurance Enough?
Some sellers may offer indemnity insurance when paperwork is missing.
However, indemnity insurance does not confirm that the extension is structurally sound or that it was built correctly. It also does not replace a structural inspection.
The buyer should discuss the policy with their solicitor and check:
What the policy covers.
What exclusions apply.
Whether the mortgage lender accepts it.
Whether further technical checks are required.
What Should You Do?
If an extension has no Building Regulations paperwork:
Find out when the extension was built.
Check whether Building Control was involved.
Ask the local authority about available records.
Check whether planning permission was required.
Speak to your solicitor if you are buying the property.
Consider a structural inspection.
Ask whether a regularisation certificate is possible.
Final Thoughts
An extension without Building Regulations approval should be investigated, but it does not automatically mean that the extension must be removed.
The key is to establish whether approval was required, whether the work is structurally sound and what options are available to resolve the missing paperwork.
Getting professional advice early can help avoid delays, unexpected costs and problems when selling or remortgaging the property.
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