How to get Retrospective Building Control Certification.

Article updated, November 2025

We get many enquiries on this, usually from homeowners in the process of selling their home. As the sale proceeds, they realise that works carried out at some point in the past (more on that below) need Building Control Approval. 

That said, a major player, Assent - a private building control firm have just gone into administration leaving thousands of owners without a certifcate after they have completed their building work.

Can they get approval on these previous works? 

The short answer is, Yes. But there are issues. 

In the first place, there are some works which may not need approval. Some may have been carried out before the regulations required them to be approved, and some may have been carried out before Certificates of Completion were introduced - legislation requiring their issue came into force in 1992.

Lacking certification in these scenarios may be excusable where there is a clear demonstration of when and what works were carried out. The problem may be compounded where over a period of time, different contractors built on, altered, or improved the original works.

What about works that were carried out more recently, when building control approval certainly was a requirement, but not obtained?

There maybe various reasons why no certificate was issued - perhaps the client was unaware they needed one, the contractor didn’t tell them, the approved inspector became insolvent during the application, or the budget simply didn’t allow for building control. 

To be clear, since 1985 there have been two ways to obtain building regulations approval (this means the same as building control). Through either the local authority or through private companies known as approved inspectors.

The two bodies offer different forms of certification for works that have been approved, inspected and passed. Where the work has been undertaken with the council's approval, the document is a Building Regulations Certificate of Completion. Where an approved Inspector is used, the document is a Building Regulations Final Certificate. 

So, the common scenario is that works were undertaken without obtaining either of these two forms of certification. Eventually the house is put up for sale and it’s at that point the problem comes to light. 

The big picture is: A buyer without certification can find themselves in a very expensive and time-consuming remedial process putting things right. Section 36 (6) of the Building Act 1984 allows a local authority to seek an injunction to remove or improve the works - the power is being used more increasingly within certain local authorities (more on this below). 

So, an extreme put-off for any purchaser, which usually leads to a fall through of sale. 

So how does it get sorted? 

There are two ways. The effective way and the insurance way. In the latter scenario it is possible for the buyer to obtain an indemnity insurance to cover these costs if they arise. The insurance is problematic, however. It only covers the one sale and only the pursuance of legal action from the local authority – it does not cover the unvalidated construction work itself. The problem with the property remains and if a buyer does actually make the purchase, they will have to address the deficiency. 

The effective way is to obtain a Regularisation Certificate which is the method by which a retrospective building control application is made.

Significantly this can only be submitted through the local authority. Approved Inspectors are not regulated to undertake this work.                

The authority may ask for certain works to be ‘opened up’ for their building control officers to make adequate inspection. They may require non-compliant work to be rectified and, they will charge for the service at a higher rate than if the application had been made at the time of the construction.                 

Certificates were made mandatory in 2013, they did exist before, as a requirement for conveyancing solicitors to demonstrate construction works were compliant with the Building Acts. Consequently, whilst a local authority may accept an application for certification for works carried out prior to this date, there’s no obligation for them to issue one. That said, this happens rarely.             

Please feel free to contact US HERE,  if you would like to talk about a retrospective building control application.