Insights 29th July 2024 Building Consultancy

For building owners with mixed-use assets, the new building control regime under the BSA  for High-Risk Buildings presents challenges that the current law and process is not nuanced enough to handle; leading to potential penalties and uncertainty, Matthew Osborne, Partner and Fire Advisory Lead writes in EG.

By now, owners of high-risk buildings are well-aware of their obligations under the Building Safety Act 2022. This defines high-risk buildings (HRBs) as buildings with at least two residential units, which are at least 18 metres in height or have at least seven storeys. Certain uses are specifically exempt from the regulations.

However, owners of HRBs may not be aware of the more onerous and time-consuming building control regime they may need to adhere to when refurbishing commercial units that are contained within high-risk buildings, or buildings that may become so following planned works.

Where works require consent from the Building Safety Regulator (BSR), the BSA requirements can currently mean delays of up to four months, compared to the usual more expeditious timeframe through the usual approved inspector or Local Authority channel.

This includes building work to an existing building which will make it a higher-risk building (for example adding storeys) or for a building undergoing a change of use.

In particular, the Building Safety Act contains provisions for building control procedures that apply to building work to an existing HRB; building work to a non-HRB (e.g. converting a five-storey residential building to a seven-storey residential building); a material change-of-use (e.g. an office-to-residential conversion) where it becomes an HRB.

Extra hurdles – and some exemptions

Higher-risk buildings are subject to the requirements of the new regime, directly overseen by the BSR. The building control approval application applies to HRBs and requires an approval from the BSR for works to commence (Gateway 2).

For example, the extra hurdles can come into play for seemingly minor or unrelated works to HRBs, such as refitting a ground-level retail space, or a Cat-A office refurbishment, which may require BSR consent due to shared structure and interlinked staircases.

It’s worth bearing in mind that there are exemptions where the unit benefits from no direct access into other parts of a building, containing residential elements (i.e. no shared staircases etc) or where the structure is wholly independent. There are also special arrangements around certain in-process projects that qualify for transitional provisions, which allow projects to stay under the previous building control regime.

Factor in new timescales

In practice, building owners need to factor this potential three to four-month application timescale into project programmes, while also ensuring that they have an expert team to prepare robust information and submissions to avoid any further delays.

When dealing with potential or existing occupiers, the knock-on effect is that building owners also need to consider the implications of approval timescales for any relevant heads-of-terms or agreement-to-lease considerations.

The building cannot be occupied until a completion certificate has been issued, and in order to receive the completion certificate (Gateway 3), the client must demonstrate that the works have been carried out according to the approved plans.

Additionally, contractors’ appetite for this process is likely to diminish, with many now unlikely to accept responsibility for gaining building control approval. Development funding agreements and building contracts may now need to factor this in.

PBSA could bear the brunt

This is particularly important for Purpose Built Student Accommodation (PBSA) developments, which typically aim to achieve Practical Completion towards the end of August, allowing occupation for the academic year. Under the new regime this can no longer happen, and developers will need to plan the construction work to complete much earlier, for example anywhere between April and June.

Look out for our upcoming article on how the process affects student accommodation developments.


What do building owners need to consider?

To ascertain their responsibility, building owners will need to consider the following three criteria:

  1. Use criteria: What is my building used for? Does it meet any of the included or excluded categories of building? For example, care homes are currently included, whereas the majority of hotels are not.
  2. Legal definition of building: How does the building definition in Regulations apply to my building structure?
  3. Height and storeys: How do the methods for measuring height and storeys in the Regulations apply to my building? Does my building meet either the 18-metre or seven-storey height threshold, when measured using these methods?

Pathway to mixed-use HRB solutions

The main differences between applying for Building Regulation Approval for high-risk buildings versus non-high-risk buildings are outlined here.

Find Out More


Matthew Osborne

Matthew Osborne, Partner and Fire Advisory Lead

This article first appeared in EG.


Find out more:

Building Safety Act