Ten years after the devastation of Black Saturday, building design has largely been unrecognised as an area worthy of research. We have advanced our knowledge of the materials used in the construction of homes in bushfire-prone areas but we continue to use the design model of the suburban home.
This needs to change. An initial starting point is to consider the way previous bushfires have damaged and destroyed buildings.
A bushfire has five different elements: smoke, wind, embers, flames, and radiant heat (the latter two are collectively called the “fire front”).
Smoke and wind are usually present throughout a fire, but are particularly high when the fire burns at its most intense levels. Depending on the type of vegetation burning, isolated flying embers may arrive hours before a fire front. Intense ember attacks usually occur 15-30 minutes before a fire front arrives, and may persist for up to 8 hours after the fire front moves on.
Radiant heat at a level that makes it impossible to survive outside will persist during the passage of the fire front, which may last anywhere between 2 and 15 minutes. However, if consequential fires are ignited by the main fire front, the radiant heat may remain at non-survivable levels for much longer.
The smoke of a bushfire reduces visibility and can turn a bright day into night. A change in wind direction can renew a threat residents thought had already passed them.
Most people would expect that the most destructive element of a bushfire is the fire front, but rather surprisingly that’s not the case. Ember entry and associated spot fires, rather than direct flame contact, accounts for 75-80% of homes destroyed by bushfires.
Embers can be large strips of burning bark, or a tiny spark as small as a pinhead, and depending on wind speed these can travel up to 10 kilometres ahead of the fire front.
Australian research over the past 75 years has revealed more than 20 different parts of a house and its surrounding area that are vulnerable to bushfire attack. Much of this knowledge has now been incorporated into a recently updated Australian Standard: Construction of buildings in bushfire-prone areas.
These guidelines aim to reduce the vulnerability of each part of a house, and thus make the structure as a whole more resistant to bushfire damage. The Standard applies across Australia for new homes and renovations.
The known weak parts of a building are referred to as the “building ignition points”. Several are considered below:
In domestic homes the roof cavity is the large open space under the roof and above the ceiling. Embers in this space can cause fire to spread rapidly, making the whole building vulnerable to ceiling collapse.
Any gap in the roof, such as a poorly secured tile, can allow flying embers to enter. The burning crown of a nearby tree, pushed onto a roof by high-speed winds, can also ignite the house.
When people choose to shelter in their bathrooms they often forget the ceiling is particularly vulnerable there. It’s difficult to access a roof cavity with a fire hose, and extinguishing embers and fire invariably damages electrical wiring, plasterwork, and home contents.
Regular inspection and maintenance of roof elements can help reduce ember entry. Avoiding trees close to your house, and removing any overhanging branches, can also help reduce this bushfire risk.
Overhanging trees can cause compacted leaf litter to build up in gutters. During a bushfire flying embers land in this material, catch alight and spread flames to combustible parts of the roof structure such as wooden facia boards, rafters, roof battens, and eaves.
It’s a good idea to clear out your gutters each year as part of seasonal bushfire preparation. Some people choose to wait until a bushfire is approaching to do this, but going onto your roof for the first time in semi-darknes while embers are flying at you can put you at risk, and endanger your life.
If you’re building a new structure you can consider extending the roof line and having a water collection system on the ground to remove the need for gutters.
Vents and weep holes
Together vents and weep holes allow for fresh air to pass through a building and for excess moisture to leave, reduce condensation and mould. They are necessary for our comfort and health, and maintaining the integrity of a building.
However in a bushfire these types of external openings can allow flying embers to enter the building and start spot fires. Having steel or other non-combustible mesh with small holes in front or behind vents and weep holes can reduce the bushfire risk while still allowing air and moisture to pass through.
Often houses constructed in bushfire-prone areas are built on a sloping block of land. The area under the building (the subfloor) is left open rather than being enclosed, and combustible materials are often stored there. The danger is similar in scale to embers in the roof cavity. When embers or flames take hold in this subfloor area they can spread under the entire building and allow the fire to move up.
Plants and mulched garden beds next to the home
Garden beds and timber steps near a house are a potential danger during a bushfire. Plants with dense foliage can burn intensely and cause radiant heat damage, cracking and imploding nearby windows and glass doors.
Garden beds which have been recently mulched can trap flying embers and spread fire to timber subfloors. It’s much better to have a non-combustible paved area next to your home, with pots containing either succulents or plants with thin foliage.
Deciding whether to stay and defend a home or leave early is a difficult and contentious choice. Hopefully, knowing more about some parts of your house which are most vulnerable to bushfire attack will make that decision easier.
California is burning, again. Dozens of peoples have been killed and thousands of buildings destroyed in several fires, the most destructive in the state’s history.
Why do wildfires seem to be escalating? Despite president Donald Trump’s tweet that the California fires were caused by “gross mismanagement” of forests, the answer is more complex, nuanced, and alarming.
The current California fires reflect a complex mix of climate, social, and ecological factors. Fuels across California are currently highly combustible due to a prolonged drought and associated low humidity and high air temperatures. Indeed, it is so dry fires burn freely through the night. Such extreme weather conditions have the fingerprints of climate change.
Compounding the desiccated fuels are the seasonally predictable strong desert winds (the Diablo and Santa Ana) that help fires spread rapidly towards the coast.
Low density housing embedded in flammable vegetation has created an ideal fuel mix for these destructive fires. Having people scattered across the landscape ensures a steady source of ignitions, ranging from powerline faults to carelessness and arson, making fires a near certainty when dangerous weather conditions arise.
Decades of wildfire suppression have created fuel loads that sustain intense fires. That these fuels are burning in late autumn is even more alarming. Under severe fire weather forest fires can engulf entire communities, with fires spreading from house to house, and human communities turning into a unique wildfire “fuel”. Suburbs can burn at the rate of one house per minute .
The standard response to wildfires is to fight them aggressively, using a military-style approach involving small armies of fire fighters combined with aircraft that spread fire retardant and saturate fire-fronts with water. Such approaches are extraordinarily costly. Annual spending on fire fighting has been steadily rising. In the US, annual fire-fighting costs now exceed several billion dollars, with individual fire campaigns costing ten to over a hundred million dollars.
Although industrial fire-fighting approaches currently enjoy political and social support, the strategy is economically unsustainable. And they are impotent in the face of climate change driven fire disasters such as those currently occurring in California.
Across the fire science community there is growing recognition this “total war” on fire approach has failed. The key to sustainable co-existence with flammable landscapes is instead managing fuels around settlements, and stopping wildfires from starting in the first place.
Spain and Portugal are good examples of why this is so important. In these Mediterranean lands, humans have sustainably co-existed with flammable landscapes for thousands of year. However, the near ubiquitous depopulation of rural lands following the second world war has led to the proliferation of flammable vegetation that had previously been held in check by intensive small-scale subsistence agriculture.
With the loss of this traditional agriculture Mediterranean countries are now experiencing regular fire disasters (such as the 2018 Greek fires and the 2017 Portuguese and Spanish fires). These are equivalent to fires in more recently settled flammable landscapes in the Americas and Australia.
This seems to be the story in most flammable landscapes on earth: the removal of traditional landscape management by colonisation and globalisation has combined with climate change to turn these landscapes into tinderboxes.
But just as it is unrealistic for Australia to faithfully restore Indigenous fire management practices, expecting a return to historical practices in the Mediterranean is not realistic. There is little economic or social reason for people to return to traditional rural lifestyles, and the gravitational pull of the social and economic advantages in urban areas is too great to stem rural depopulation.
But we can adapt traditional practices to help us live with fire. In the Mediterranean, people are already experimenting with different ways to manage landscapes, such as managing forests for cork and bioenergy, combined with prescribed burning and grazing.
This can create picturesque landscapes that are fire-resistant and easy to defend. Similarly, in Australia, the Victorian government has created parkland-like green fire breaks that were used for back burning operations to protect communities during 2009 Black Saturday wildfires.
The Hobart City Council is planning to use similar fire breaks to protect its outer suburbs with dense bushland. Such management could be used on a larger scale to substantially reduce fire risk. The challenge for landscape fuel management is providing financial and regulatory incentives for citizens and local communities to reduce fuel.
Currently, no society is sustainably co-existing with wildfire. Globally, the situation will worsen under a rapidly-warming climate with ballooning firefighting costs, and huge loss of life and destruction of property. This is the bitter lesson of the Californian fires.
Nigerian police arrested 164 people in connection with a mostly-Christian slaughter of 500, reports MNN. There are 41 charges of terrorism and homicide. With a movement toward justice, is the trouble over?
Todd Nettleton with Voice of the Martyrs likens the violence to a wildfire. "The government or the military comes in and puts a lid on it for a while, and then there’s another breakout. "
Former Nigerian President Olusegun Obasanjo has said that the violence is fueled more by ethnic, social, and economic problems than by religion.
That may be true, but Nettleton adds: "The level of violence in this case–the fact that it seems to have been a very coordinated effort against Christians–says probably it will happen sooner rather than later, and that it will break out somewhere else."
Some have claimed the attacks were in retaliation for the killing of more than 300 Muslims earlier this year around the same city. Then, on March 17, Muslim herdsmen disguised as soldiers butchered nearly a dozen Christians in two villages near Jos, setting some of them ablaze.
Mainly women and children were killed in both massacres. There are reports that indicate youth are calling for revenge against the Muslims.
VOM supports the persecuted church there. Their team is helping hundreds of Nigerian pastors who continue to spread the Gospel of Jesus Christ despite persecution. VOM also provides food, clothing and medical aid to Nigerian Christians who are attacked by Muslim extremists.
The threat of violence won’t stop their work. Nettleton says, "There is going to be some care given to how and where they meet, especially in light of fact that these were clearly coordinated attacks. But there is still going to be a Christian presence there, and there are going to be believers who are reaching out, who are sharing their faith, and who are praying, even for their persecutors."
Report from the Christian Telegraph
Adding to the recent arrest of two Christian Iranian women, Iranian security forces recently raided an underground church in Karaji and arrested five Muslim converts to Christianity, reports MNN.
Among them was the church leader, Javad Abtahi. During the raid, plainclothes security officers confiscated several Bibles and then handcuffed the Iranian Christians and took them to an unknown location.
Jonathan Racho, regional manager for Africa and the Middle East with International Christian Concern, said, “We believe that the latest arrest shows that there is a spike in persecution against Christians in Iran.” This “clamp down on Christians,” as he called it as well, also includes the arrest of two Iranian women, Marzieh and Maryam, back on March 5.
The location of these women is known as they are being held in the “notorious Evin prison,” Racho said. The prison is located in Tehran, the capital and largest city of Iran.
Since the five Christians were arrested, there still has been no news as to their location. A relative of one of the five asked official for a location, but the official would not give them the information.
“There is no news about their release, so we assume that they are still imprisoned,” Racho said. Thus, he said they believe the Christians could be facing any sort of hardship at the hands of the Iranian officials.
Racho recently said, speaking to ASSIST News, “Iran should refrain from invading Christian houses, arresting converts and confiscating their properties. Iran must allow its citizens to choose what religion to follow. We call upon Iranian officials to release the five Christians arrested in Karaji as well as Marzieh and Maryam.”
Though the church in Iran now must be more careful than ever where and when they meet, the recent arrests have not stopped the Gospel from spreading in Iran.
“It has not stopped Christianity from spreading in Iran. We have information that Christianity is truly spreading like a wildfire in Iran,” Racho said. “Many Muslims—thousands of Muslims—are coming to Christ, thanks to the courage of Iranian Christians who are working very hard to spread the Good News.”
Racho and the rest of ICC ask you to pray for revival in Iran as many more Iranian Muslims come to Christ. He also asked everyone to pray for the safety and release of the five Christians and the two women, Marzieh and Maryam, earlier arrested.
Report from the Christian Telegraph