Australia — Ian Weir isn’t the first West Australian ever to buy a plot of bushland and build a cabin or two. But he might be the first who is actively hoping his buildings get hit by the full force of a bushfire.
Dr Weir, a research architect at the Queensland University of Technology, is pioneering a new idea in bushfire-proof building design one aimed at allowing residents to ignore the traditional advice handed out by fire authorities about how best to protect property.
He is building two experimental structures on a bushland plot on the Point Henry Peninsula, south of Bremer Bay and nestled among thousands of hectares of bushland.
The region coincidently where Dr Weir also grew up – was hit by an out-of-control bushfire in December 2012, during which homes on the peninsula were declared ‘undefendable’ by fire officials.
His prototype buildings are designed to withstand the full fury of the “flame zone” as a bushfire passes by.
“This is really, for a lot of people, a mind-bending proposition they’re actually designed to be burnt,” he said. In fact, from an aesthetic point of view, he says he won’t consider his buildings fully complete until they have acquired the charred patina left behind by a bushfire.
Techniques include constructing buildings on stilts, using fire-resistant concrete slabs; covering windows with shutters to keep heat and flames out; and partitioning roof spaces to individually insulate different areas of the structure.
These features also help with other, more everyday considerations, such as heat insulation and energy efficiency. But the idea, Dr Weir explains, is to design these everyday features in such a way that the building defends itself in the event that a bushfire arrives.
That means there is no need to stay and defend properties, no need for local firefighters to risk their lives defending the building, and most controversially no need to follow the standard advice about clearing nearby vegetation.
“I’m fundamentally not interested in clearing vegetation just to achieve bushfire safety, because there are a lot of problems with that approach other than just taking away the nice trees. There’s no actual guarantee that that will actually protect your house,” he said.
It’s an attitude that has, perhaps understandably, provoked condemnation from fire authorities. The official advice remains to minimise risk to properties by clearing nearby vegetation.
The WA Department of Fire and Emergency Services advises maintaining a 20-metre “circle of safety” free from dry grass, bark and debris, as well as pruning nearby trees.
But Dr Weir says that what he calls the “mantra” of vegetation clearing is part of a “top-down” culture that discourages homeowners from assessing the situation and then preparing for the worst by designing the right kind of house.
“There’s absolutely no guarantee that a fire and emergency services vehicle is actually going to come to your property. So why not design the house so that it can just do it’s own job, regardless of whether somebody comes or not?” Dr Weir said.
“And naturally we’re talking about evacuating early and not having anyone risk their lives to protect a property. That’s an area where I’m happy to work with local authorities.”
Bushfire-proof buildings are not a new idea, of course. In the 1970s, Sydney-based architect Glenn Murcutt was designing homes in the Blue Mountains with inbuilt water ponds that have stood the test of numerous fires.
As more traditional homes are destroyed by fire, architecture critic Philip Drew has argued that they need to be replaced with entirely bushfire-proof communities. “To fail to do so is madness in a time of climate change,” he wrote.That madness, he said, is “mandated by cultural habit and a delusional longing for the familiar”.
Yet bushfire-proof houses still need to look and feel like houses, Dr Weir said. “Designing for daily patterns of use is where we really have to go with bushfire design in this country. Architects have to create simple houses that work,” he said.
That’s why he rejects “bunkeresque” building designs, with tiny windows and huge expanses of bare rammed earth. In fact, the whole idea of bushfire bunkers can be counterproductive, he said.
“Of course there have been some great survival stories from Black Saturday of people retreating to their bunkers. But to design just a standard off-the-shelf house in a really exposed bushfire site and then just whack a bunker in out the back, that’s just not really intelligent thinking because in that time of emergency and that could be 20 years’ time who knows if that bunker’s going to work?”
The two cabins that Dr Weir is building in on Point Henry peninsula cost around $50,000 and $150,000, for small structures of just 25 and 60 square metres, respectively.
But he hopes that the principles can be scaled up to create houses that can be used in fire zones all over the world.
“The fundamental issue is that there is no guarantee that somebody will go and protect your property. People should really understand the risk themselves and take responsibility for it.”