Bridging the Gaps Between Structural and Fire Engineering

According to the latest CROSS-UK Topic Paper, ‘Mind the Gap: Bridging the Gaps Between Structural and Fire Engineering’, some of the greatest risks in modern building design arise not within disciplines, but at the interfaces between them.

Drawing on the expertise of CROSS-UK’s Fire Safety Expert Panel, published research, industry guidance and reports from built environment professionals, the Topic Paper examines where ‘disconnects’ emerge between structural and fire engineering and how they affect building safety. While focused on the Building Regulations 2010 and Approved Documents in England, the findings are relevant across the UK’s construction sector and beyond.

Its central message is simple: safer buildings require closer collaboration, clearer accountability and a better understanding of how structural and fire safety interact throughout a building’s lifecycle.

Critical interface

Structural and fire engineering have traditionally evolved as separate disciplines. Structural engineers ensure buildings remain stable under normal and accidental loads, while fire engineers focus on fire behaviour, smoke movement, fire resistance periods and evacuation.

In practice, however, the disciplines are closely interconnected. Structural decisions influence fire safety strategies, while fire performance depends on how a building’s structure behaves under fire conditions.

As buildings become taller and more complex, and performance-based design becomes more common, unclear responsibilities at this interface increase the risk that important issues remain unresolved.

Post-Grenfell challenge

The Topic Paper comes at a time of significant change for the construction industry. Since the Grenfell Tower fire, reforms have placed greater emphasis on competence, accountability and managing safety risks, shifting the focus from demonstrating compliance towards demonstrating that risks have been properly identified and managed.

Against this backdrop, the Topic Paper asks whether current approaches to structural and fire engineering consistently deliver the outcomes intended by the Building Regulations. It concludes that important gaps remain, particularly so where responsibilities overlap.

Gaps to be bridged

The Topic Paper identifies six areas where disconnects commonly occur:

*Legislation: Regulations establish separate safety objectives for ‘structure’ and ‘fire safety’, potentially reinforcing a siloed approach between structural and fire engineering disciplines

*Guidance: Standards are often developed from individual disciplinary perspectives, in turn leading to fragmented approaches where structural and fire assumptions may not align

*Scope of services: Project teams may assume another consultant is addressing an issue, leaving responsibilities between disciplines undefined and critical tasks overlooked

*Insurance: Professional Indemnity Insurance arrangements can discourage consultants from engaging with issues perceived to sit outside their formal remit

*Competence and knowledge: Engineers need sufficient understanding of each other’s disciplines to recognise interfaces, identify conflicts and seek specialist input when required

*Industry co-ordination: Poor communication between consultants, contractors and specialists allows assumptions to go unchallenged and risks to remain hidden

Collectively, these gaps show that structural fire safety is as much about communication, co-ordination and accountability as technical design.

Limits of prescriptive design

The Topic Paper also examines the growing use of performance-based design. Traditional prescriptive requirements, such as minimum fire resistance periods, provide a clear route to compliance, but complex buildings increasingly require more flexible and performance-based solutions.

These approaches depend on assumptions about fire scenarios, structural behaviour and performance criteria. If those assumptions are not shared and understood across disciplines, significant risks can arise. A fire engineer may develop a strategy based on one set of assumptions while a structural engineer designs to another, with the mismatch only becoming apparent late in the project or after occupation.

The Topic Paper therefore argues that Parts A and B of the Building Regulations should be treated as complementary, with fire recognised as an accidental action and structural performance assessed under realistic fire scenarios rather than relying solely on prescribed fire resistance periods. This is particularly important for complex or high-consequence buildings.

Many assumptions about structural and fire performance are made during design, but lose value if they’re not properly recorded and communicated. Years later, building owners or refurbishment teams may not understand the rationale behind key decisions, increasing the risk that alterations compromise safety.

Maintaining clear records of assumptions, responsibilities and design decisions is a fundamental part of building safety, not simply an administrative task.

From compliance to confidence

Ultimately, the Topic Paper is less a technical guide than a call for a more integrated and risk-based approach to structural fire safety. It advocates earlier collaboration, clearly defined responsibilities and better communication throughout a building’s lifecycle, duly encouraging engineers to apply informed judgement and seek specialist expertise where needed.

The message is clear: compliance alone is not enough. Safer buildings depend on structural and fire engineers working together to ensure that critical issues don’t fall between disciplines. By closing these gaps, the industry can move beyond compliance towards greater confidence in the safety and resilience of the built environment.

*Collaborative Reporting for Safer Structures UK (CROSS-UK) is a confidential reporting system which allows professionals working in the built environment to report on fire and structural safety-related issues. These reports are then published anonymously to share lessons learned, create positive change and improve safety. Further information is available online at www.cross-safety.org/uk