Auckland could need an extra 20,000ha to accommodate new houses in the next three decades if its current style of new housing is to continue.
Martin Udale, ex-chief executive of McConnell Property, was commissioned by Ree Andersen, Auckland Council's regional strategy manager, to write an independent review of a report by Studio D4's Patrick Fontein and architects Jasmax on the controversial plan to ring-fence 75 per cent of all new housing within existing city limits in the next 30 years.
The council wants about 300,000 of the 400,000 new houses it expects the city to need within the next 30 years to rise within the town boundaries, a plan opposed by many commercial developers as not viable.
Udale, of Essentia Consulting Group, also questioned the wisdom behind the plan and raised the prospect of just 15 new houses built on each hectare of land, many small-lot suburban housing and townhouses, and showed how the city would need an extra 20,000ha.
But if 25 houses were built on a hectare and terrace-style residences were a big part of the mix, 12,000ha of land was needed. If 100 dwellings were built on each hectare, just 3000ha of extra land would be needed, he calculated.