Queensland researchers have deliberately set timber ceiling compartments alight at temperatures reaching approximately 1,000 degrees Celsius, in a series of controlled experiments designed to improve fire safety standards for a new generation of timber buildings. The tests, conducted at the Queensland Fire Department's training ground at the Port of Brisbane, were supervised by firefighters and monitored with live-streaming cameras alongside heat and pressure sensors.
Why Timber Buildings Pose a Unique Fire Safety Challenge
The research is being led by University of Queensland PhD candidate Josh Madden, who has a background in fire safety engineering. He says the rapid growth of mass timber as a building material has exposed a significant gap in existing fire safety guidance.
"Current fire safety guidance was generally built around the assumption that structural materials don't burn," Mr Madden said. "But the issue with timber is that timber actually burns."
Mass timber, which is made from engineered layers of wood compressed, glued or nailed together into uniform panels and slabs, has become an increasingly attractive option in the construction sector. It can be fabricated off-site and assembled quickly, unlike concrete, which requires weeks to cure on-site. As Mr Madden describes it, timber construction can function much like assembling Lego bricks. That speed and flexibility, however, comes with fire behaviour that existing safety frameworks were not designed to address.
Timber begins to lose structural strength at around 60 degrees Celsius and loses virtually all strength from roughly 300 degrees Celsius onwards, making its behaviour in a fire fundamentally different from steel or concrete.
Inside the Experiment: 12-Metre Compartments and Controlled Ignition
Each test compartment measured approximately 12 metres in length and 2.5 metres in width, constructed from cross-laminated timber. Researchers altered design variables between tests, including ventilation conditions and ceiling height, to observe how those changes affected fire spread.
"We essentially ignite the fire down one end and watch how fire spreads underneath the ceiling," Mr Madden said. Temperature readings from the instruments climbed to around 1,000 degrees Celsius during the experiments, which Mr Madden described as a genuinely eye-opening experience even for someone well versed in the theoretical side of fire engineering.
"It was a pretty unreal experience," he said. "For me, being a researcher, I know all the theory behind it. It was pretty eye-opening."
The project forms the centrepiece of Mr Madden's PhD and sits within a broader program of work at the ARC Research Hub to Advance Timber for Australia's Future Built Environment. The University of Queensland and the Queensland Fire Department have maintained a formal information-sharing partnership since 2014.
Benefits for Firefighters as Well as Engineers
QFD fire engineer Mick Conway said the collaboration offered practical benefits that extended beyond academic research. Controlled burns give firefighters direct exposure to how new materials behave in extreme heat, knowledge they might otherwise only encounter for the first time in a real emergency.
"By burning materials under experimental conditions, our firefighters are learning things that they otherwise might have had to experience for the first time in a live scenario," Mr Conway said.
He emphasised that understanding new materials and innovative design approaches was essential to building safer timber structures as their use in construction continues to grow. For more on increasing safety in built environments, further reading is available on this site.
What Comes Next: A Framework for Confident Timber Design
The test results are still being analysed and will form part of Mr Madden's final thesis. The ultimate goal is to produce a practical design methodology that fire safety engineers can apply with confidence when planning mass timber structures.
"What we're trying to develop is this sort of design methodology or framework for fire safety engineers to go out and have the confidence to be able to build these buildings," Mr Madden said. "If we have the knowledge and expertise to be able to design these safely, hopefully the idea will be that we'll see lots more of these beautiful massive buildings."
