When Fire Engineering Becomes Justification, Not Design

Fire engineering is intended to be a design tool. A means of developing solutions that achieve clearly defined fire safety objectives.

But there is an uncomfortable reality.

It is sometimes used the other way around.

A design decision is made first. The fire engineering then follows, not to shape the outcome, but to justify it.

This is not a theoretical concern. It has been observed in practice for many years, and it remains relevant today. The drivers are not difficult to understand. Commercial pressures, architectural ambition, and programme constraints can all influence design decisions before fire strategy is fully developed.

At that point, the role of the fire engineer becomes critical.

If the engineer is engaged early, with clearly defined objectives and appropriate authority within the design team, fire engineering can guide the design towards a robust and balanced outcome.

If not, there is a risk that it becomes an exercise in validation.

The distinction is subtle, but important.

Design-led fire engineering asks: what is the safest and most appropriate solution for this building?

Justification-led fire engineering asks: how can we demonstrate that this design is acceptable?

The difference lies in intent.

In a justification-led approach, there is a tendency to select assumptions, scenarios, or modelling inputs that support a preferred outcome. The process may still appear rigorous. Calculations are undertaken, models are run, and reports are produced. But the direction of travel has already been set.

This creates a credibility problem.

Fire engineering relies on judgement, interpretation, and the application of models with known limitations. Where the process is used to support a predetermined answer, rather than to explore a range of outcomes, the reliability of the conclusions becomes questionable.

The issue is not the tools. It is how they are used.

In the years following Grenfell, there has been a necessary focus on competence, transparency, and accountability within the fire safety profession. These are essential. But they do not, on their own, address the underlying behavioural issue.

That requires something more fundamental.

Clarity of objectives. Independence of thought. And a willingness to challenge the design, not simply support it.

This is not always easy in a commercial environment. Fire engineers are part of a wider design team, and there can be pressure, implicit or explicit, to align with project objectives. However, the role of the fire engineer is not to make the design work at any cost. It is to ensure that the fire safety strategy is appropriate, defensible, and aligned with the agreed objectives.

Where that alignment cannot be achieved, it should be said.

Fire engineering is a powerful tool when used properly. It enables innovation, flexibility, and improved outcomes.

Used incorrectly, it risks becoming a mechanism for explaining why a weak design is acceptable.

That is not a technical failure.

It is a professional one.

This article is informed by long-standing industry research and evolving practice. The views expressed are those of the author and are intended to support learning and good practice.