A Guide to Higher Risk Buildings

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Estimated reading time: 10 minutes

Author: Becky Wootton, Architect BArch (Hons) Dip Arch

ARB registration no. 085383F

Becky is an associate at Architecture for London and she also leads our construction teams. She has direct oversight of site progress, ensuring design quality and low-energy strategies are carried through to each completed home.

Contact me: 020 3951 9790

Introduction

This article explains the process of making alterations, improvements and extensions to higher-risk buildings.

In response to the tragic Grenfell Tower fire in 2017, significant changes have been made to building safety regulations to reduce the likelihood of events like this from occurring again. The Building Safety Act 2023 was introduced to improve safety regulations – specifically for higher risk buildings (HRBs).

Whether you’re a homeowner in a high-rise building or a construction professional, it’s important to understand the new safety regulations and legal responsibilities.

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What is a higher-risk building?

A higher-risk building can be defined as one that is at least seven storeys tall, has a top floor level of more than 18 metres above ground level and contains two or more residential units. These buildings might be privately owned, rented or a mixed-use building with residential elements.

The Building Safety Regulator (BSR) is a new body that was introduced to oversee the safety and standards of high-risk buildings. They are part of the HSE (Health and Safety Executive).

The BSR is responsible for regulating HRBs during design and construction, and occupation, ensuring and improving the competence of design and construction professionals. They raise safety standards and respond to resident concerns regarding overall building safety.

Proposed alterations to a flat in a high-risk building in Whitelands House, Chelsea, SW3

Residents are now more involved with the safety of the buildings they occupy. A residents’ panel has been established under the BSR, and it gives tenants and leaseholders in HRBs a way to raise their concerns about the safety of the building they live in. They provide feedback based on guidance provided by the BSR and encourage accountability and transparency from building managers. Residents are also able to raise concerns to an accountable person, such as a landlord, management company or freeholder.

Registered Building Control Approver and Dutyholder roles

A role that has been newly introduced is a Registered Building Control Approver – this role has replaced “Approved Inspectors”. These registered approvers must obtain a licence from the BSR to ensure they meet the required competency standards.

To create clear accountability throughout the building process, specific Duty Holder roles within a project have been identified:

Client – the person for whom the project is carried out. They must ensure the appointed professionals are competent and qualified.
Principal Designer – the lead designer responsible for design and health and safety during the design phase (This is a separate but parallel role to the CDM Principal Designer)
Principal Contractor – lead contractor and responsible for health and safety on site during the construction phase. Ensures all subcontractors follow the correct safety procedures (This is a separate but parallel role to the CDM Principal Contractor)
Designer – an organisation or individual that prepares and modifies a design for a construction project, including the design and temporary works. Must report to the Principal Designer.
Accountable person – responsible for managing building safety risks, such as fire or structural safety, once construction is complete and the building is occupied.

Principal Designer Responsibilities:

Plans, manages and monitors design work during the design phase, ensuring all designers comply with their responsibilities and comply with building regulations.
They must liaise with other designers to eliminate foreseeable health and safety risks to anyone affected by the work, and try to manage risks.

Principal Contractor Responsibilities:

Plans, manages and monitors building work during the construction phase and coordinates matters relating to building work.
They manage the health and safety risks during the construction phase.
They work with the principal designer and ensure risks are managed effectively.

Building safety regulator approval

Building Safety Regulator approval must be granted before works begin. The client can nominate someone to make the application for approval; however, ultimately, it is their responsibility to apply.

Approval is needed for:

The construction of a new high-risk building
Building work to an existing building that makes it a higher risk, or stops it from being a higher-risk building
Work to an existing HRB (including work within a single flat within an HRB)

Approval usually isn’t needed for:

Repair work
Replacement of baths/ toilets/basins
Installing insulation in roof spaces
Replacing gutters or downpipes

Proposed alterations to a flat in a high-risk building in Whitelands House, Chelsea, SW3

Applying for Building Safety Regulator approval

The BSR should take 12 weeks to assess applications for new higher-risk buildings and 8 weeks to assess applications for existing higher-risk buildings. However, in reality, currently, the assessment times are much longer.

Following approval, if your building work has not made significant progress within 3 years, then you will lose approval for the work.

Cost structure

Costs are – £180 charge with application; plus £144 per hour worked for BSR staff; plus any costs to BSR of relevant authorities and third parties. The BSR will not supply an estimate of hours or costs.

Higher risk buildings: application requirements

You must submit one application per building, and if you are planning to carry out multiple building works in one building, only one application is needed. Likewise, if the building work is carried out on multiple HRBs that are connected by one shared podium, area or common part, only one application is needed.

https://www.gov.uk/guidance/preparing-information-for-a-building-control-approval-application

You must submit an online application, and it must include the following details:

Applicant and project team details – Names and information for the applicant, client, principal designer and principal contractor
Building information – name, address, site location, lan, post works, building height and storeys
Scope of works – description (max 2000 characters), estimated build time and the number of residential and non-residential units
Drawings and plans – these drawings must describe the project and the details of the work involved, explain the scope of works and show how the work complies with building regulations.

Proposed alterations to a flat in a high-risk building in Whitelands House, Chelsea, SW3

Higher risk building applications: compliance documents

Building regulation compliance statement
Must show the approaches that are being taken to ensure building regulations are met
Fire compliance statement
Change control plan – this includes details of how changes to the approved design will be dealt with. Unplanned changes can risk compromising compliance and can change the outcome which was approved by the BSR. These changes must be approved before proceeding with the works
Construction control plan – this demonstrates how the HRB works will be managed so it aligns with the relevant requirements. It should include strategies for evidencing compliance and good communication between designers, contractors and the client
This outlines how the client will monitor and manage construction to make sure compliance is maintained
It must detail strategies, policies and procedures the client has set out to manage and monitor HRB work and how the client has supported the cooperation between designers, contractors and other subcontractors involved with HRB work

Competence declaration documents

The client must confirm that they have taken all reasonable steps to check that the principal designer is competent enough to carry out their duties
The client must ask those working on the project if they have been sanctioned by the HSE in the last 5 years

Categorising your work

It is important to apply using the correct category; otherwise, the BSR will reject your application.

Category A – Major work such as:

Changing the external height or width of the building
Changing the number of storeys
Altering the internal layout
Changing the number of residential units
Work that involves passive fire safety measures – fire-resistant materials
Work that involves active fire safety measures – alarms, sprinklers
Work that affects the number or width of staircases or other escape routes
Work on building common areas – including work on external walls

Category B is any other work that does not fit into Category A.

Proposed alterations to a flat in a higher-risk building above 18 metres, in Queens Gardens, W2

Gateways and the “golden thread”

The new process includes three key gateways:

1: Securing planning permission relating to fire safety
2: Securing building control approval
3: Securing a completion certificate

Gateway 1 ensures that fire safety has been considered at the earliest stage of the design and planning process. Gateways 2 and 3 are set up to be hold points – to ensure that safety is being considered at each stage of the building processes.

A “Golden Thread“ of digital information must be maintained. This system tracks all safety-related details throughout the life of the building.

Phased applications for complex projects

If working on a multi-building scheme, a staged application may be beneficial, as each stage corresponds with the construction stages. Each stage is assessed as if it were an application for a separate building. Building works must not start until it has been approved by the BSR.

Phase 1 ‘Staged work statement’: includes a description of the first stage of work and a summary of the work beyond that first stage, the subsequent stages statement.

Subsequent stages statement should include:

Detailed plans and drawings
Updated subsequent stages document – which sets out work occurring beyond the stage that’s currently being applied for
Updated partial completion strategy if one was submitted as part of the building control approval application
An estimate of when each stage will start

Higher risk buildings: works on a smaller scale

An installer registered with a Competent Person Scheme can carry out specific works in accordance with the standard Building Regulations, without needing to apply to the BSR. You should notify the local authority of the work and be issued a certificate of compliance within 30 days of completion.

Works that are covered by the Competent Person Schemes (refer to the CPS website for a detailed list):

Installation of cavity wall and solid wall insulation
Installation of gas appliances
Replacement of windows, doors, and roof windows/lights in homes
Replacement of roof coverings on pitched and flat roofs
Electrical insulation work in dwellings

However, it is currently difficult to find Competent Person Schemes that will verify works in HRBs.

The Building Safety Act 2022 – A Summary

The concept of a higher-risk building is a new provision introduced under the 2022 Building Safety Act. This legislation is grounded in the 2022 Safety Regulations, which aim to enhance building safety across all stages of construction and provide stronger protections for residents, particularly in high-rise developments.

The Act places a strong emphasis on structural integrity and fire safety—issues that were highly scrutinised following the Grenfell Tower tragedy. By addressing these concerns, the legislation seeks to drive improvements in the design, construction, and ongoing management of higher-risk buildings.

https://www.legislation.gov.uk/ukpga/2022/30/contents

https://www.legislation.gov.uk/ukpga/2022/30/part/4

We are currently working on a number of projects in higher-risk buildings in London. If you would like to discuss your project, please contact us.