As understanding about the likely impacts of climate change continues to develop, concern about its impact on the built environment continues to grow.
A report published in 2010 by the Australian Building Codes Board found that while the nation could be reasonably confident about the capacity of buildings currently constructed in compliance with Building Code of Australia standards to be reasonably resistant to the effects of global warming under a low emissions scenario (in which temperature rises were limited to 1.8 degrees Celsius in Australia by 2070), this was not the case with regard to the more likely higher emissions scenario (3.4 degree temperature rise).
The report noted at the time that the higher emissions scenario was the more likely outcome and that, if realised, many buildings constructed under today’s standards would be deficient.
In addition to the environmental effects, this will have legal and financial effects upon a number of industry stakeholders.
One critical area revolves around insurance. Rising sea levels and more common extreme weather events are not only expected to impact the overall risk level (and therefore the amount of premiums charged to insure certain properties) but are also impacting how risk is calculated and spawning growing levels of effort on the part of the insurance sector to better understand specific risks at an individual property level. The issue is also leading the insurance sector to price insurance products for residential property on the basis of considerations which are specific to that property as opposed to those which are general to a pool of properties (i.e. a whole suburb) within a local area.
Toward this end, the industry is currently developing Building Resilience Rating Tool which - when complete - will provide a resilience rating of individual properties by taking into account not only area specific factors such as local weather hazard risks but also the characteristics of the individual site as well as the type of house and building materials used.
Tom Davis, director and co-founder of social and environmental consulting outfit Edge Environment, said the upshot of this will mean that how houses are designed and constructed will increasingly impact upon the insurance premiums owners will expect to pay, and that the importance of architects, builders and designers delivering homes which are designed to withstand extreme weather events or natural disasters will only intensify going forward.
“Ultimately, it will stimulate the building supply chain – the architects, the engineers, the planners – to start developing more appropriate houses,” Davis said. “There is nothing wrong with building in a flood zone (for example) - Australians have been doing it for years - as long as you are building the appropriate house within that flood zone."
Also of concern are the legal impacts. DLA Piper special counsel Mark Baker Jones said effects will be felt not so much by designers or developers (provided buildings comply with the Building Code of Australia and are fit for purpose when sold) but more so for local councils, who could potentially face litigation in cases where the wrong type of development was approved in the wrong area.
Baker said one complicating factor for councils revolves around constant shifts in broader planning policy at the state level, which has in some cases negatively impacted the ability of councils to accommodate climate change considerations in local planning rules.
He noted that a key example could be seen last year in Queensland, where then-Deputy Premier Jeff Seeney instructed the Moreton Bay Regional Council to remove a paragraph that cited a potential 0.8-metre sea rise in its draft regional plan. Baker said this created an apparent contradiction in which the council was obligated to take global warming into account when approving new buildings but was not able to include a reference to rising sea levels within its planning scheme. Seeney argued that climate change concerns would be better resolved by variations in individual development applications as opposed to an ‘across the board’ planning provision.
Baker said a further area of concern arises from council responsibilities under legislation revolving in large part around what is considered to be reasonable – a standard which potentially changes and evolves in the case of climate change as more becomes known about global warming.
“So, for example, if you are a council decision maker, there is a danger of relying on historical practices where climate change hasn’t been factored in,” Baker said. “What was reasonable 10 years ago may not be deemed to be reasonable today because of that increase in knowledge about climate change. The goalposts have changed.”
Davis said the critical ways in which architects and the design community can help clients and other stakeholders mitigate the impact of climate change revolve around incorporating resilience and consideration of potential local hazards into the construction which takes place.
“It’s about the design community acknowledging or identifying what the key hazards are in their particular area and mitigating those hazards in their design,” he said.