Foreword
In recent decades, with the development of sustainable development practices and energy efficiency, modern architecture has developed rapidly. However, raising the priority of fire safety is less important, and we need to reconsider our approach.
Combustible coating materials often found in buildings pose a safety hazard. The system originally used to help solve this problem is not good enough. Therefore, my colleague and I have created a library of cladding materials, an online database that provides insight into the flammability of various cladding materials. Cladding materials used in modern rain protection systems outside buildings provide insulation and protect buildings from rain, wind and sunlight. They also allow architects to create interesting architectural designs, such as by adding vivid colors or curves to the outside.
However, in addition to other shortcomings, the flammability of modern siding materials has led to an increasing number of fires worldwide. For example, the 2014 Lacrosse Fire in Melbourne and the Grenfell Tower Fire in London in 2017.
The seriousness of the problem
Many of the cladding materials currently in use are flammable to varying degrees, including the very common aluminum-plastic composite panels (ACP). These have a plastic-based core material (such as polyethylene) and have an aluminum plate attached to either side. Although ACP is sometimes almost non-flammable, it is generally considered to be flammable. In Queensland, approximately 18,000 buildings have been inspected to determine the flammability of the cladding and the overall response of the building to the fire. Of these, 75% do not need to take further action. For the remaining 25%, engineers were hired to investigate further whether they had problems.
The Queensland Government estimates that 100 to 200 buildings need to be made safer, while a building can cost tens of millions of dollars. It is important to note that some buildings use a flammable coating, otherwise they have a strict fire protection design, for example, the fire door network is well maintained, the escape distance is short, the firefighter access is good, and the layout minimizes the risk. Therefore, having a flammable cover does not necessarily mean that the building is dangerous. Nevertheless, such materials should not be included without the architects, engineers and builders correctly understanding the risks involved.
To help us, we developed a database
The database created by me and my colleagues is the first such database, which provides detailed information on the flammability information and material properties of different types of common cladding materials. Often, the same materials are reused in buildings because too many products are available on the market. We used a small scale test (10 cm sample) to determine which material is most important. However, identifying materials is not sufficient to understand its performance in a fire. Therefore, we completed the flammability test (samples not exceeding 1 m in length) for 20 materials commonly used outside the building.
In one year, we extracted 1,100 small material samples from the building and conducted 9,250 tests. We then identified 75 unique cladding materials and narrowed them down to 20 materials, which were then tested in detail (30 tests for each material). We have chosen a wide variety of materials to ensure that the most common materials appear in our choices. Our experiments involved exposing the material to heat in a controlled manner and then changing the heat to see how the sample responded. Our process involves measuring the time it takes for a material to catch fire, how much heat is released from the material, how it is released, and how the flame spreads. Our results are now publicly available in a library of cladding materials that can be updated as new materials are invented. The database will help fire engineers assess the potential fire risks of buildings.
Writing accurate reports is critical
Fire engineers can use our database to determine the overall performance of a building in a fire. Then they may ask the following questions:
How long will the fire spread in the building?
Can people arrive at a safe place in time?
Is there any flammable substance near the important escape route?
If the fire spreads upwards, how will the rest of the building work?
However, fire engineers involved in such surveys also need ongoing training to update their knowledge. For many, this is a continuing professional development program designed by the University of Queensland and a similar course offered by the Queensland Government for building professionals such as builders and architects. The latter is critical to the success of our project because it enables building professionals to understand current issues and reports written by engineers.
On the last day of the summer of 2019, the Victorian Civil and Administrative Tribunal (VCAT) delivered a ray of sunshine to the apartment owners in the high-rise hockey net building in Melbourne’s Docklands. The lacrosse ball suffered a severe fire on November 24, 2014, due to a cigarette on the balcony. On Thursday, Judge Ted Woodward ordered an immediate payment of $5.7 million in damages to the landlord. The judge also stated that the owner would receive most of the balance of its A$12.7 million claim, including a compliance cost of nearly $6 million. However, in our confrontational legal system, there are both losers and winners. In this case, the loser is a fire engineer, certifier and architect.
The builder, LU Simon, was sentenced to pay more than $5.7 million to the owner of the apartment. However, after Judge Woodward found that they had breached their contractual obligations, the architects, fire engineers and building certification agencies working on the project would pay the majority to Lu Simon. Firefighting engineer Thomas Nicholas was ordered to pay 39% of the damage, the creator Gardner Group compensated 35%, and architect Elenberg Fraser compensated 25%. Incredibly, the builder LU Simon is the winner and is estimated to have paid only 3% of the compensation.
Future security
Currently, fire engineers hired by government or building owners are making immediate changes to related buildings to improve their short-term security. In the end, they will make suggestions on how to improve long-term building safety, which may cost more time and money. The only way to solve the fire risk is to understand the performance of each building and have a qualified engineer responsible for its design.
Our research will represent changes in the way we solve the problem and is expected to prevent fires in the future.
