Infrastructure capacity, not zoning, is increasingly a major constraint. Many established suburbs were not designed to absorb the scale of growth now being targeted, and upgrades to drainage, sewerage, transport, schools, open space and community infrastructure are complex, costly and poorly sequenced.

The assumption that infill is inherently more cost-effective than greenfield is increasingly difficult to defend. Infill only works where genuine spare infrastructure capacity exists. Once that capacity is exhausted, retrofit costs escalate quickly, shifting costs onto government and taxpayers, while greenfield often provides a more transparent, sequenced and deliverable infrastructure pathway.

Melbourne is not tracking toward 70/30. Recent delivery patterns show a much more balanced split between established areas and growth areas, reflecting the practical constraints facing infill delivery.

The “missing middle” remains missing. Townhouses and low-rise infill are meant to play a central role in established suburbs, but the redevelopment pipeline has weakened through lower turnover, fewer demolitions, higher costs and reduced builder capacity.

Apartments cannot carry the strategy. High-density apartment projects are commercially viable in only a very narrow set of locations, with construction costs, finance costs and buyer capacity creating a major feasibility gap across much of Melbourne.

Greenfield development remains a necessary part of the solution. Growth areas are continuing to deliver housing at scale and increasingly provide a broader mix of housing types. Rather than treating this as a policy failure, government needs to support well-planned growth-area delivery while reforming the systems required to improve infill outcomes over time.