By March 2020, when Australians could finally exhale at the end of the Black Summer, the country’s unprecedented bushfire season had destroyed nearly six thousand buildings.
Thirty-three people would lose their lives in the bushfires, including nine firefighters, as a country desiccated by two years of drought began to combust. The average national Forest Fire Danger Index in 2019 was the highest on record; if these felt like the worst fires in memory, the evidence says they were. As much as 40 million hectares of Australia burned, and nearly three billion animals are now thought to have been killed or displaced.
The disaster was foreshadowed by early winter bushfires in Central Queensland, and more than 3,000 fires would blacken 7.7 million hectares in the south, north and far-north of the state by Christmas.
Before the south-eastern states burned through December and January, Queenslanders had endured a day, November 9, on which a State of Fire Emergency was declared across 42 local government areas. For a second severe Queensland summer in a row, news crews and onlookers had stood by the wreckage of homes and wondered why they had been destroyed and their neighbours spared.
The impact of fire on buildings
It is a question that occupies Justin Leonard. The CSIRO Bushfire Adaptation lead researcher has spent decades analysing the impact of fire on buildings through several lenses, including that of an engineer. Put another way, he views risk from a community’s perspective, rather than from the fire’s. On present trends, there is cause for concern.
“The gap between the small proportion of the community that have a deep knowledge of how to manage their surrounds in a bushfire and the rest is not narrowing over time,” Mr Leonard says.
“We need to design houses that can survive fire without defending them, and this can only happen if people have a deep understanding of how fire interacts with the house. So, understanding how bushfires behave and impact buildings is essential.”
The path of increased resilience is, increasingly, winning support in the sunshine state. The State Government has today introduced a 10-step Bushfire Resilient Building Guidance for Queensland Homes[Link will open in a new window], outcomes of a project led by Mr Leonard.
A broad coalition of agencies and experts has contributed to the guideline, from the Queensland Fire and Emergency Services, to local government, and James Davidson architects.
CSIRO’s bushfire research pedigree is renowned. The national science agency published its first post-bushfire-related paper in 1944 and has performed post-fire surveillance and research for every major fire event in Australia since Ash Wednesday in South Australia and Victoria in 1983. And Mr Leonard says this latest science-driven, best-practice resource for homeowners works in concert with individual Bushfire Survival Plans and steps beyond the state’s official building regulations.
The 10 steps of the new bushfire guidelines begin with learning the “essentials” about bushfires and their behaviour and culminate with maintaining bushfire-resilient properties in ways intended to become as natural for Queenslanders as swimming between the flags.
The guideline’s 10 steps are:
Step 1: Bushfire essentials
This encourages Queenslanders in fire-prone areas to know the environments where bushfires occur, the different types of fires and how building are typically impacted, and how to assess hazards in and around a property.
Step 2: Bushfire survival plan
Already familiar to safety-minded Queenslanders, the guideline highlights the importance of developing a bushfire plan to protect occupants and to prepare home to survive a bushfire.
Step 3: Bushfire hazard assessment
This step unlocks tools to understand the bushfire hazard at people location, such as bushfire risk postcode checkers, bushfire prone area location, and tools to calculate potential radiation levels (including Bushfire Attack Level, BAL) , as well as busting myths around bushfire – for instance, that removing trees is the best way to slow the spread of fire.
Step 4: Building category
Categorises projects into building a new house or fixed structure; retrofitting an existing house or structure; and landscaping the area around a new or existing house or structure.
Step 5: Siting and site layout
Emphasises the importance of choosing the best locations for buildings on the available land, while making considerations for bushfire resilience, site access, and aesthetic values and preferences.
Step 6: Bushfire resilient design principles
Provides a toolbox of design solutions that are graded into four levels of protection, with Level Four designed to guard against ember attack, burning debris, fine fuel surface fire of any height, direct flame contact from a bushfire front, and “consequential fire” such as car or neighbourhood house burning down.
Step 7: Bushfire resilient construction
Informs homeowners about bushfire-resilient construction systems including those for walls, floors, roofs, windows, doors and verandas and decks and provide example of construction design.
Step 8: Bushfire resilient materials
Identifies the main material used in common building types, such as concrete, masonry, cladding, decking, supports describing the advantages and disadvantages of the material to reduce ignition from embers, radiant heat and flame,
Step 9: Bushfire resilient landscaping
Encapsulates fire-resistant landscaping advice from garden layout and the right plants, to landscaping that shield a home from embers, heat, flame and wind.
Step 10: Maintenance
Outlines useful habits to adopt at home including keeping twigs and leaves out of rooftops and gutters, checking gutters and rooftiles for damage, clearing vents of debris, preserving the seal between roof and wall junctions, and keeping roof cavities clear of combustible materials.
The new resilient building advice provides Queenslanders with the latest advice to protect their homes from fire, in line with the equivalent guides to storm tide, cyclones and floods.
Experts on risk, though, warn against any complacency in places like eastern Australia and California, where many communities are racing to adapt to bushfires on a scale they have never seen.
“Understand risk,” says Dr Robert Glasser, former head of the UN Office for Disaster Risk Reduction.
“The past is no longer a reliable indicator of what lies ahead; even assumptions about who you can rely on for support need to be questioned.”
For Mr Leonard, a truly adapted community means far more than a collection of buildings and homes built to tolerate fire. To be safe and useful in a fire, he says, an individual’s knowledge and understanding is the key. After all, it is they who can decide to prepare their house, not to be there, or if they stay, to shelter in the right place or work with others.
“It takes a whole lot of enlightened, active individuals who share their knowledge within the community, offer local context,” Mr Leonard says.
“Understanding spreads through the community; a community conversation about how to consider the bush beyond the back fence.”
You can read more about the Bushfire Resilience Building Guidance for Queensland Homes here[Link will open in a new window].
This article was originally posted on December 11, 2020 and has been updated for the current edition.