Structural Fire Engineering: Definition, Importance and Methods

Structural engineering is a well-established discipline, as is fire engineering. However, the specialized field of structural fire engineering (SFE) is less widely known, despite its critical role in designing fire-resilient buildings.

Unpacking Structural Fire Engineering: What It Is and Why It Matters

There is no single universally accepted definition of SFE. According to Lennon (2011), it is an amalgamation of the two older disciplines of structural engineering and fire engineering to ensure better prediction of building behaviour in the event of a fire, and better overall design for fire safety.  

In simple terms, SFE can be understood as the advanced design of structures to withstand fire conditions. The level of complexity varies depending on the project. In some cases, it involves refined hand calculations to determine the critical temperatures of steel elements, rather than defaulting to the conventional assumption of 550°C. In more intricate applications, it requires comprehensive thermal and structural numerical analyses, incorporating real fire loads and compartment characteristics that influence fire progression.

By combining structural integrity with fire safety considerations, SFE moves beyond traditional prescriptive approaches, enabling performance-based design solutions that enhance both safety and efficiency in modern construction.

Why it Matters?

There are multiple reasons to use SFE in different kinds of projects. One of the most evident benefits is the optimization of fire protection, which can lead to material and cost savings while also enhancing aesthetics — potentially allowing for more exposed structural elements.

In some cases, prescriptive fire safety methods may not be applicable, such as in product development or when working with existing or historic structures. SFE provides a more flexible and performance-based approach in these scenarios.

Moreover, as SFE means more advanced analysis of the structure and fire, it also produces more accurate assessments about the performance of the structure under realistic fire conditions. This deeper analysis helps identify critical aspects of structural fire safety while also determining where design choices — such as exposed structural elements — can be justified without compromising overall fire resistance.

SFE Methods and Applications

As previously mentioned, the application of SFE varies significantly depending on the project. While various guidelines have been developed, there is not a single approach that fits all SFE projects.

A commonly referenced principle, the “consistent level of crudeness” (Buchanan, 2008), often serves as a useful starting point. It refers to maintaining a balanced level of detail and complexity when analysing both the fire and structural aspects of a problem in SFE. However, this principle may not be fully suitable in every case. It emphasizes that the level of detail in the analysis should remain consistent between both the fire and structural aspects of the problem, ensuring a balanced and reliable evaluation.

The Interdisciplinary Nature of Structural Fire Engineering: Collaboration and Competence

SFE demands expertise in both fire engineering and structural engineering. Depending on the specific project, one discipline may play a more prominent role than the other.

It is essential that the individual or team responsible for performing SFE — or any portion of it — possesses the requisite competence for that particular task, whether it involves determining the design fire scenario or analysing the structural behaviour.

SFE typically requires collaborative efforts among a variety of project stakeholders, including the architect, structural engineer, fire engineer, structural fire engineer, client, contractor and regulatory authorities. Since SFE may be unfamiliar to many stakeholders, effective communication of the problem, approach and solution becomes a critical aspect of the process.

Reference: 

Buchanan, A. (2008). The challenges of predicting structural performance in fires. Fire Safety Science, 9, 79–90. https://doi.org/10.3801/IAFSS.FSS.9-79

Lennon, T. (2011) Structural Fire Engineering. ICE Publishing, UK