Fire Risk Assessments (FRAs) are a cornerstone of building safety — yet in many cases, they only reveal part of the story. While an FRA identifies visible risks such as blocked escape routes or missing signage, it can often overlook a far more insidious threat: hidden failures in fire compartmentation. These weaknesses lie out of sight, behind walls, above ceilings, and within service risers — but when a fire breaks out, they can make the difference between safe containment and catastrophic spread.
What Is Fire Compartmentation — and Why Does It Matter?
Compartmentation is the principle of dividing a building into fire-resistant sections designed to contain fire and smoke for a set period. These barriers — walls, floors, doors, and ceilings — allow occupants to evacuate safely and protect escape routes and adjoining spaces. When properly maintained, compartmentation prevents fire from spreading unchecked.
However, even small breaches in these fire-resisting barriers can undermine the entire strategy. A single unsealed pipe penetration, damaged fire-stopping material, or poorly fitted access panel can create a pathway for smoke and heat to spread rapidly between compartments.
A Widespread but Hidden Problem
Recent reports from the Collaborative Reporting for Safer Structures (CROSS-UK) and passive fire protection specialists reveal a worrying trend: many buildings across the UK, including relatively new ones, suffer from inadequate or missing fire stopping. Common defects include unsealed service penetrations, incomplete fire collars, and unprotected ceiling voids.
These issues are often created during later refurbishment or maintenance work, when tradespeople install new services and fail to reinstate fire-stopping properly. The result? Buildings that appear compliant on paper but contain hidden weaknesses that could prove devastating in an emergency.
The FRA Gap
A standard FRA is typically a non-intrusive, visual inspection — it won’t involve lifting ceiling tiles or opening wall cavities. As a result, it may not identify concealed compartmentation issues unless there are obvious signs of failure. This limitation means many Responsible Persons are operating under a false sense of security, believing their premises are safe when serious defects remain unseen.
To bridge this gap, a fire compartmentation survey should complement the FRA. This more detailed, invasive inspection assesses the integrity of fire-resisting elements throughout a building. It often includes photographic evidence, drawings, and recommendations for remedial work — providing the full picture of a building’s passive fire protection.
Closing the Gaps
Addressing compartmentation failures isn’t just about compliance; it’s about protecting lives and property. Building owners and managers should:
Looking Ahead
As the Building Safety Act and recent updates to the Fire Safety Order place greater accountability on duty holders, the days of “surface-level” compliance are over. True fire safety requires understanding what lies behind the walls as well as what’s visible in the corridors.
A building may look safe — but unless its compartmentation is properly inspected, tested, and maintained, your FRA might only be telling half the story.
If this article has highlighted concerns about your building’s fire safety, our CHPK Fire Engineering team can help. We provide detailed compartmentation surveys, fire risk assessments, and tailored guidance to ensure your buildings meet current legislation and best practice.
Get in touch with us today to arrange a consultation or discuss your fire safety strategy.
