Performance-Based Fire Engineering: When You Need It

What You Need to Know

Not every building fits the standard fire safety rules. When the NCC's Deemed-to-Satisfy (DtS) provisions do not work for your design, a performance solution fills the gap. A qualified fire engineer analyses the building and proves it meets the NCC's safety objectives through engineering, not just prescriptive rules.

• The NCC allows two compliance paths: DtS provisions or Performance Solutions. Both are equally valid (NCC Part A2.2)
• Performance Solutions must follow a structured process: brief, analysis, evaluation, and report (NCC A2.2(4), effective 1 July 2021)
• A Performance Based Design Brief (PBDB) must be agreed with all stakeholders before analysis begins. This is a mandatory hold point (NCC A2.2(4))
• Four assessment methods can demonstrate compliance: evidence of suitability, verification methods, comparison with DtS, or expert judgement (NCC A2.2)
• The Australian Fire Engineering Guidelines (AFEG 2021) published by the ABCB provides the accepted methodology. It replaced the older IFEG 2005 for Australian use
• The Fire Engineering Report (FER) becomes a fire safety measure for the life of the building. A copy must stay on-site at all times

You need a performance solution when DtS provisions conflict with the building design. Common triggers include travel distances that exceed DtS limits, open-plan floors larger than the allowed fire compartment size, and atriums connecting multiple levels. Heritage buildings, warehouses with high storage, and change-of-use projects also frequently need them.

For a Class 5 office building, DtS allows 20 m travel to an exit or 40 m total to a choice of two exits. Many modern office floor plates push past these limits. A fire engineer can model the actual fire and smoke behaviour, prove the evacuation time is safe, and justify longer travel distances with compensating measures like sprinklers, smoke detection, and wider corridors.

The process has two stages. First, the fire engineer prepares a Fire Engineering Brief (FEB) that sets out the scope, the DtS deviations, the analysis methods, and the acceptance criteria. All stakeholders sign off before any modelling starts. Second, the Fire Engineering Report (FER) contains the full analysis: fire modelling, evacuation calculations, and the engineered solution that meets the NCC Performance Requirements.