Of that total, 4600 will be sold on the open market. It was initially thought that 20 per cent of them would be sold at affordable levels, defined as less than $650,000.
But Social Housing Minister Amy Adams told the Herald yesterday that 20 per cent was a minimum requirement, and developments would be up to 50 per cent affordable housing.
Asked why the developments were not made 100 per cent affordable, Adams said there needed to be a range of prices to get buy-in from developers who would be building and selling the homes.
She said there would be no further developments on the scale of Tamaki and Hobsonville, where construction of 4000 homes is already underway. The newer developments would mostly be 40 to 100 houses in size.
Opposition parties have raised concerns about property speculators snapping up the new homes. But Adams said there would be strict limits on who could buy the affordably-priced houses and how long they could own them for before reselling.
"Our interest is ensuring that people are buying them to live in them, and to live in them for some time."
They were likely to be limited to first-home buyers and some of the developments, including the Axis project at Hobsonville Point, would be restricted to New Zealand citizens and residents.
The programme is the Government's biggest push yet to address dire housing shortages in the city.
The building programme is not as ambitious as Labour's policy, which is to build 50,000 Auckland homes over 10 years, all of them in the affordable range. That is part of a plan to build 100,000 homes nationwide, which was first announced by former leader David Shearer in 2014.
Labour leader Andrew Little said yesterday that National's plan would not keep up with Auckland's population growth of 100 more people a day. It failed to prioritise families and first-home buyers, he said.
Adams said she doubted whether Labour's plan was feasible. The Government's policy was based on two years of research into the amount of land available and the capacity of the building sector.
It was not possible to build more houses without creating ghettos or poorly-designed, overcrowded developments, Adams said.
"Could you squeeze more properties onto the land if you could find the builders? Probably. Would it be a good idea? No.
"This is the total amount that can feasibly be built on Crown land over the next 10 years if we still care about the quality of the communities we are creating."
There is an estimated shortfall of 40,000 houses in Auckland to meet current demand.
Adams said it was not solely up to Government to address this supply gap, and it was only a "small player" in Auckland's house-building sector.