Infill development three times cheaper than greenfield, report finds

Architecture AU

Written by Louisa Wright

17th August, 2016


A report has found that developing Perth’s greyfield sites alongside rapid transit networks could save the government up to $94.5 million for every 1000 lots developed, compared to developing greenfield sites.

The report, Design Perth, is a joint study between the Property Council of Australia, the Office of Senator Scott Ludlam, CODA Architecture and Urban Design, and Curtin University Sustainability Policy Institute (CUSP).

The large savings come from the difference in cost to government in providing infrastructure such as roads, water, communications, power, emergency services, health and education. The report found that for greenfield sites the cost is $150,389 per lot while greyfield sites cost $55,828 (almost three times less) due to much of the infrastructure already being in place.

Increasing Perth’s infill target from 47 percent to 60 percent (the original target under the WA government’s 2014 Network City plan) will save $23 billion before 2050.

The Design Perth report compared current development to transit-oriented development with a proposed Light Rail node. In comparing these, the study found that the latter delivered a:

260 percent increase in the number of dwellings and residential population
352 percent increase in commercial space and employment
187 percent increase in public open space and 27 percent more homes within 200 metres of green space
335 percent increase in active frontage
Significant increase in dwelling diversity with 52 percent more low- and medium-rise apartments
CODA worked with students from the University of Western Australia to research the areas identified as future transport corridors in the draft State Transport Strategy. All sites selected were greyfield sites that, with the addition of public transport, had the potential for high-quality amenity.

A one-day intensive design charrette was held and eight design teams, including engineers and planners, were each assigned a site and given the task of preparing initial design responses to present to an expert panel. The designs included design options for different housing and commercial spaces, and identified limitations by current policy that might prevent the design from coming to fruition.


Co-founder of CODA, Kieran Wong, said out-of-date urban policy designed for low-density suburbs was not allowing for innovative design-led solutions. The average age of local planning policies in Perth is 14 years.

“I think the major challenge for the state is to try and upgrade planning policies at a local level or provide some kind of overriding state policy around best design and better medium-density outcomes that applicants and developers can use. At the moment we’re in a bit of limbo because the local policies are really inefficient and too old,” Wong said.

In June 2016 the West Australian government released its public transport plan, Transport @ 3.5 Million, but Wong said the plan does not address significant challenges in relation to the provision of light rail and rapid bus transit. He said a targeted approach towards public transport should be taken to accommodate for the development of greyfield sites.

“You can see the numbers in a sense, where growth occurs in other cities around Australia and around the world, it’s all linked to an underpinning of solid public transport networks and that’s something that the state needs to commit to,” said Wong.

Community consultation was also key to the design process. Wong said typically in Western Australia, the community was either consulted at the very beginning of the development process and then ignored, or consulted at the end and told what was going to happen.

“That in a sense is something we consider to be part of the issue in relation to community protest around infill, that [the community is] not part of the conversation all the way through. In a sense they’re almost viewed as a kind of impediment to development and we’re trying to turn that model on its head a little bit in this report,” he said.