Fire Safety Considerations for Change of Use Projects
Across the UK, offices are becoming apartments, industrial buildings are being transformed into mixed-use developments and older commercial properties are being adapted to meet changing demands. As developers increasingly choose to repurpose existing buildings rather than demolish and rebuild, change of use projects are becoming an important part of delivering new homes and commercial space.
Government figures illustrate the scale of this trend. During 2024/25, 17,710 additional homes were created through change of use in England, including more than 5,000 office-to-residential conversions completed under permitted development rights.
As the number of change of use projects continues to grow, ensuring buildings remain safe for their new purpose is becoming increasingly important. While many of the principles of good design and construction remain the same, adapting an existing building requires project teams to approach fire safety differently. Rather than working with a blank canvas, designers and contractors must understand how the existing building has been constructed, how it has evolved over time and how proposed alterations may affect its overall fire strategy.
Why Existing Buildings Require a Different Approach
One of the biggest misconceptions surrounding change of use projects is that they simply involve adapting the layout of an existing building. In reality, changing the purpose of a building can fundamentally alter how it needs to perform in the event of a fire.
Unlike new-build developments, where fire safety measures are incorporated into a coordinated design strategy from the outset, existing buildings often contain hidden complexities. Buildings may have been extended, refurbished or altered several times throughout their lifetime, often under different Building Regulations and construction standards. Original drawings may no longer reflect the building as it exists today, while concealed voids, ageing materials and undocumented alterations can all influence how the building performs in the event of a fire.
Changing a building's use can also introduce different occupancy patterns, escape strategies and regulatory requirements. A former office converted into residential apartments, for example, presents different fire safety considerations than when it was originally designed.
For this reason, understanding the existing building is an essential part of any successful change of use project. Before refurbishment begins, project teams should assess the building's existing fire protection measures, identify where they may have been compromised and ensure any proposed alterations maintain the integrity of the overall fire strategy.
Why Passive Fire Protection Matters
Passive fire protection forms an integral part of a building's overall fire strategy.
Unlike active fire protection systems, such as alarms or sprinklers, passive fire protection is built into the fabric of the building itself. It is designed to slow the spread of fire and smoke, maintain structural stability and protect escape routes, providing valuable time for occupants to evacuate safely and allowing the Fire and Rescue Service to respond effectively.
Key components of passive fire protection include:
Fire compartmentation
Fire stopping around service penetrations
Fire-resistant walls, floors and ceilings
Fire doors
Cavity barriers
Structural fire protection
Fire dampers
Each component performs a specific role, but together they create a coordinated fire strategy designed to contain fire and smoke, protect escape routes and safeguard the structural integrity of the building. The effectiveness of that strategy depends on every element working together as intended.
Small Alterations Can Have Major Consequences
During refurbishment, even relatively minor alterations can affect a building's fire performance if they are not carefully considered.
For example, installing new electrical services, plumbing or ventilation systems often requires penetrations through fire-rated walls and floors. Unless these openings are correctly reinstated using appropriately tested fire stopping systems, the original level of fire resistance may no longer be achieved, allowing fire and smoke to spread beyond the compartment.
Similarly, damaged cavity barriers, gaps above partition walls, incompatible products or poorly installed fire stopping systems can all reduce the effectiveness of passive fire protection.
Many of these issues remain hidden once construction has been completed, making quality assurance, competent installation and effective coordination between all trades essential throughout the project.
Looking Beyond Compliance
As the number of building conversions continues to increase, understanding the existing building becomes just as important as designing its future. Every alteration should be considered not only for its architectural or structural impact, but also for how it affects the building's overall fire strategy.
By considering passive fire protection from the earliest stages of design, maintaining effective fire compartmentation and ensuring all fire stopping systems are correctly installed, project teams can help deliver buildings that are not only compliant with current regulations, but safe, resilient and fit for their intended purpose.
Ultimately, successful change of use projects are about more than transforming existing buildings. They are about creating spaces that continue to protect the people who live, work and visit them long after construction has been completed.
