How Our Bushfire-Proof House Design Could Help People Flee Rather Than Risk Fighting the Flames
How Our New Design Can Withstand Fire
The prototypical bushfire resistant house we designed won first prize in the New Housing Division of the United States Renewable Energy Laboratory’s Solar Decathlon.
The house would be made from locally sourced, recycled steel frame. It would be mounted on reinforced concrete pilings to minimize its disturbance on the land, touching the ground only lightly. In this way, we help preserve the site’s biodiversity.
The primary building material is rammed earth – natural raw materials such as earth, chalk, lime, or gravel – which is not combustible.
The roof and some cladding are made of fire-resistant corrugated metal. Its glass facades have fire shutters made of fiber cement sheeting, a material that’s non-combustible and can be closed to seal the house.
Importantly, the gaps between these construction materials are 2 millimeters or less.
The sloped roofs tilt inwards to capture rainwater. And as the roofs are made of corrugated metal, which has channels in it, the house does not require gutters.
These channels guide rainwater into two open retention ponds either side of the entry, and into protected tanks beneath the house. This also helps protect the house in a bushfire, as it means the fire can’t penetrate from beneath.
When bushfires strike, the risk to life is highest when people stay and defend their homes. A design that can resist fire on its own encourages its owners to leave.
But it’s worth noting that it’s not a bunker for people to shelter in. No matter how well designed a house is, it always will be too dangerous to stay when a fire comes through, and particularly in the catastrophic and extreme fire conditions we’re increasingly experiencing.
It’s Cost Effective, Too
The estimated cost of construction is between A$400,000 and $450,000. We deployed several strategies to keep costs down:
· the house is designed to be energy and water independent, so will not need city utilities
· it uses common construction techniques and is based on the construction industry standard for sheeting, so won’t require specialised builders and won’t waste any material
· rammed earth is relatively inexpensive because it can be sourced in many locations, often for free. We also envision using recycled materials wherever possible.
Aesthetically speaking, the design also presents an elegant domestic space, one that’s flexible enough it can easily be adapted to almost any site.
The next stage is to build and test a prototype of the house so we can evaluate its performance and make improvements. We’re currently speaking to some potential funders to make this happen.
As climate change brings worsening disasters, Australia must brace for thousands more houses becoming destroyed. Innovative architecture like ours offers a chance for treasured homes and possessions to survive future catastrophes.
Deborah Ascher Barnstone is Professor, Head of School, School of Architecture, University of Technology Sydney.This article is published courtesy of The Conversation.
