To solve Australia’s complex urban challenges, from housing affordability to climate resilience, engineers and planners must look beyond regulation and embrace a more active, educated, and intentional role in development, argues a Queensland University of Technology (QUT) expert.
Australia’s cities are under pressure. Faced with rapid population growth, a deepening housing affordability crisis and the urgent need for sustainable, climate-resilient development, the pressure on our urban planning systems has never been greater.
A common argument for the way forward is to relax zoning regulations, allow for more density, and let the market deliver the affordable, sustainable housing we need.
However, according to Dr Mark Limb, a senior lecturer in Urban and Regional Planning at QUT’s Faculty of Engineering, this story is an incomplete one.
“The claims we hear around the restrictions of zoning and what that means for house prices are often ideological and theoretical in their basis,” Limb said. “It’s taken for granted that zoning is a restriction, that restriction equals less supply, and less supply equals higher prices. My research, and that of others, suggests it’s not that simple.”
Limb’s work challenges this conventional wisdom. A landmark study he co-authored with Dr Cameron Murray, examining 20 years of zoning changes and development outcomes in Brisbane, found that upzoning for density was actually associated with higher house prices, not lower ones. The research, which analysed over 25,000 sites, showed that while zoned capacity for new dwellings doubled over the study period, a staggering 78 per cent of sites with that capacity remained undeveloped.
The reason, he argues, is that Australian planning policy has become too focused on facilitating market activity rather than correcting market failure. The system is designed to enable development, but it lacks the mechanisms to compel it.
“Zoning locates where development can go, not when it is developed,” he said. “Ultimately, that is something left up to the market. When you leave things to the market, you end up with what the market does best: it allocates goods to those with the highest propensity to pay for them.”
This leaves the provision of a critical public good – housing – to a market that increasingly treats it as a financialised asset, with development timed to maximise profit when prices are high.
The result is a system that excels at negative controls – stopping a factory from being built next to a school, for example – but struggles to proactively deliver positive, strategic outcomes for the community, Limb said.
Taking a more intentional approach
Limb points to international examples where the state takes a more direct, entrepreneurial role in development to achieve strategic goals.
“If we want specific housing outcomes, then we need to consider directly provisioning them,” he said. “In a more affordable past in Australia, we had far higher amounts of state housing provision.”
In Singapore, for instance, the state’s housing corporation builds huge volumes of dwellings, with 80 per cent of citizens owning a home delivered by the state developer. This direct involvement allows for the seamless integration of land use, transport, and infrastructure planning from the outset.
This shift in mindset, from passive regulator to active shaper of the urban environment, is critical. But it’s a shift that can’t happen without a corresponding evolution in the skills and outlook of the professionals tasked with building our cities.
Engineers as students of the city
For the engineers and planners at the implementation phase of urban development, this context is crucial. Limb argues that to truly move the needle on sustainable urban futures, practitioners must become more than just technical experts; they must become dedicated “students of the city”.
“The education of our urban professionals is absolutely fundamental,” Limb said. “A technically proficient engineer or planner who simply follows the rules without understanding the ‘why’ behind them can, with the best of intentions, contribute to poor outcomes. We need professionals who are educated to be critical thinkers.”
For Limb, being a “student of the city” means cultivating a deep, holistic understanding of the complex forces that shape urban environments. It’s about looking at a regulation – a minimum lot size, a building height limit, a two-metre setback – and understanding its role in the larger picture.
“It is about trying to understand the reasoning for why planning rules are there, rather than just focusing on the letter of the law,” he said.
“Those rules are a reflection of what a community is trying to achieve. It’s about being able to turn one’s mind as a student of the city towards the good outcome you’re trying to get to, and then asking, ‘How can my design and my technical expertise help deliver that outcome in the best possible way?’.”
This is particularly important in a performance-based planning system like Queensland’s, which is designed to provide flexibility. However, as Limb’s research has shown, without trust, expertise and a shared understanding of strategic goals, such systems often default to a more rigid, prescriptive process, stifling the very innovation they are meant to encourage.
“Our research on planners’ perceptions of the performance-based system highlighted that the mechanisms themselves are perhaps less important than matters of trust and professionalism,” Limb has previously written. “To make these systems work, you need highly skilled, trusted professionals on both sides of the counter – in the private sector and in government – who can have a sophisticated, outcomes-focused conversation.”
