"If you don't ... you will get anarchy. It will just be an unholy mess," he said.
Last month, Auckland councillors voted behind closed doors to loosen density controls and strengthen design controls in two residential zones in the Unitary Plan.
This was a reversal of the density controls put in place following a public backlash to the concept of no density in the lead-up to the 2013 local body elections.
Since 2013, the city's housing problems have worsened. The council has been under pressure from the Government and developers to find solutions, including relaxing the rules in the Unitary Plan.
Reserve Bank Governor Graeme Wheeler has said building height restrictions and Nimby attitudes in inner Auckland were standing in the way of an adequate supply-side response to the housing shortage.
He estimated the backlog of unsatisfied demand at between 15,000 and 20,000 houses.
Developer Mark Todd yesterday said the Auckland supply pipeline could only deliver houses above the median price.
"It is not economically viable to build smaller, more affordable units," said Mr Todd, whose company, Ockham Residential, has built several inner-city apartment blocks.
He believes unrestricted density allows for more diverse housing, more affordable options and more green space.
Last month's decisions remove density controls from the mixed housing urban zone next to town centres and transport routes, which make up about 10 per cent of residential Auckland.
Councillors also narrowly voted 8-7 to remove density controls on sites bigger than 1000sq m in the mixed housing suburban zone, about 40 per cent of residential Auckland.
Height limits stay at three storeys in the mixed housing urban and two storeys in the mixed housing zones.
Deputy mayor Penny Hulse, who has been guiding the council's Unitary Plan process, said the density issue was not easy. Councillors were on the same page as Auckland 2040 about relaxing density controls and the need to retain a strong set of urban design outcomes.
"Our concern now is to retain the ability to enforce urban design guidelines in any changes or amendments made to the Resource Management Act, Ms Hulse said.
Changing rules
Mixed housing urban - next to town centres and transport rules
Previously:
One dwelling per 300sq m and no density limits on sites greater than 1200sq m with 20m frontage. 3-storey height limit.
Now:
No density limits, but strengthened design controls. 3-storey height limit.
Mixed housing suburban - typical suburban areas
Previously: One dwelling per 400sq m and one dwelling per 200sq m on sites greater than 1200m with 20m street frontage. 2-storey height limit.
Now: One dwelling per 200sq m on sites less than 1000sq m and no density limits on sites greater than 1000sq m. Strengthened control limits. 2-storey limit.