Now called the ‘black summer’, Australia’s 2109-2020 bushfire season was the worst on record. Quite simply, the fires were unprecedented. As of March 2020, 18.6 million hectares had been set on fire, more than buildings had been set on fire (including 2,779 houses) and, more tragically, 34 people had lost their lives. On top of that, nearly 3 billion animals, including threatened and endangered species, have been killed or displaced.
Considering Australia’s love for our native bush and our tendency to build homes as close as possible, that figure of 2,779 destroyed homes could easily have been higher. If there is a silver lining to fire, it’s that over the past few years we’ve started to understand better how to build a bushfire-proof house.
Design of a bushfire-safe house – construction in areas prone to bushfires
How do you know if your house (or the land you want to build a house on) is in a bushfire area? Relevant town planning regulations vary by state (for example, in NSW you should contact the NSW Rural Fire Department, while in Vic the competent authority VicPlan).
If it turns out that you are in a bushfire area, if you want to do any construction or renovation work, you should do a Bushfire Attack Level Assessment (BAL). This involves determining the appropriate measures to be taken to ensure that the house is protected against a possible bushfire. For example, BAL 40 construction requirements are more stringent than BAL 12.5 construction requirements.
A home rating level measures the severity of its risk of attack from embers, radiant heat and direct contact with flames. BAL is measured in terms of radiant heat (kilowatts / m²).
Here are the relevant BAL notes:
- LOW Ball: very low risk
- BAL 12.5: Low risk
- BAL – 19: Moderate risk
- BAL 29: High risk
- BAL 40: Very high risk
- BAL FZ: Extreme risk
What materials are good for a safe house against bush fires?
Although there is no flame zone kit, with careful selection of materials specifiers can greatly enhance their expertise in designing bushfire-proof homes.
Cladding – In terms of exterior cladding, corrugated iron is a good choice for a fire retardant home, as are some types of fiber cement panels.
Frame – Care should be taken when using wood for decks and so on. Fire resistant woods include turpentine, red iron bark, blackbutt, merbau, red river gum. mottled gum and silver ash are recommended for house designs for bushfire areas.
Windows and glazing – It is a good idea to install exterior metal shutters on all windows. In terms of window frame materials, aluminum and metal reinforced PVC are recommended.
Steel frames – Steel frames are a good choice because they are extremely durable and fire resistant.
Exterior – Apart from that, it is also important to consider gardens and landscaping. Always make sure that there is a space of 5m between the house and the garden and place the house as far as possible from native trees, make sure that the gutters are regularly cleaned of fuel.
Install a sprinkler system – An important feature of a fire retardant home is a sprinkler system. These should spray with water which is usually pressurized at 300 kpa.
There are several myths and misconceptions regarding bushfire proof houses, among those who are not familiar with their construction. The most popular of these is that bushfire resistant houses always end up looking like a bushfire bunker. In fact, unless they are in the most dangerous places, they look a lot like standard houses. Even if you live somewhere like Kinglake, a town devastated by the 2009 Black Saturday fires, you can still build a house that is safe from the bushfires.
Bush fire proof house design – 10 of the best bush fire proof houses
1. Durimbul bushfire resistant house
Located in Wye River, Vic and designed by architect Matt Goodman, the Durimbul Bushfire Resistant House was built to replace a house destroyed in a 2015 bushfire. Although perched on a hill, it is fire resistant.
2. Bellbird retirement home
Located in Killarney in the Gold Coast hinterland of Qld, this retreat from Steendijk Architects combines a rugged, fortress-like exterior with a beautiful, light interior. Its most striking feature is its bushfire resistant roof.
4. Sydney Blue Mountains House
Designed by Urban Possible, this one-story, three-bedroom weekend was designed to deal with potential bushfires. For example, instead of having multiple windows, there are multiple, three-meter-high, tempered double-glazed pivot doors.
5. House of Mount Macedonia
Designed by Field Office Architecture, Mt Macedon House, which is located in Victoria’s Macedon Ranges, features non-combustible materials and meticulous details. For example, it is clad in Corten cladding.
6. Karri fire station
Located on a BAL 40 property, this Ian Weir home is built on stilts and has several fire-resistant features like hollow masonry walls, concrete slabs and shutter aids on the windows to cancel out the effects of heat. and flames.
7. House H
Also by Ian Weir Architect, H House is designed to hold itself (without any human assistance) during a bushfire. Led by Ian Weir, research architect and lecturer at Qld University of Technology (QUT), H House presents a model for reconciling bushfires and diversity with everyday life. H House is located in the bushfire prone biodiversity landscape of Point Henry, WA.
8. The Christmas Hills house
Designed by architect Clare Cousins and located in the town of Christmas Hills in Vic, this home replaced a home that was destroyed in the infamous Black Saturday fires. It meets the requirements of BAL-29, which is the second highest level of bushfire attack.
9. Ball-Eastaway House
Located in Glenorie on the northwestern suburb of Sydney in New South Wales, the Ball-Eastaway House was designed in 1980 by Glenn Murcutt, who was somewhat of a pioneer of bushfire-resistant homes. Its features include innovative leaf-proof gutter designs, black ceramic house tiles that reflect radiant heat, sprinkler systems and rooftop fountains.
10. Compressed earth bush fire resistant house
Winner of the Bushfire Building Council of Australia Innovation Award for Best Design Concept in 2015, this house by Baldwin O’Bryan Architects is FZ – Flame Zone certified, which is the highest level of bushfire attack. raised in Australia. It incorporates a low-cost building block system based on stabilized compressed earth blocks, which the architects envisioned. This system is not only very durable, but also considerably cheaper than reinforced concrete.