A sneak preview of the big election debate

Construction has begun at part of Fletcher Building's Three Kings Housing Development, which Labour's Michael Wood has opposed. Photo by Lynn Grieveson

There may be four months to go before the election, but it's now clear where the National vs Labour-Green clash will be most intense and meaningful: housing.

Polls show housing is the top issue for voters ahead of the September 23 election and they will face a clear choice between the National government and the Labour-Green opposition. This week's debate in and around Parliament ahead of the Budget gave a taste of a tough election campaign debate to come over housing that could easily decide the winner.

Prime Minister Bill English launched straight into an attack on Labour's Kiwibuild policy almost as soon as he arrived back in Wellington after his last big overseas trip before the election.

He accused Labour of being "unrealistic and dumb" with its promise to build 100,000 houses while at the same time opposing two large housing developments in Auckland and planning to cut migration by tens of thousands.

English referred to the government's Point England Development Enabling Bill, which is due to be read for a second time in Parliament this week and which Labour has pledged to oppose because it turns parkland into houses. English also referred to the opposition of local Labour MP Michael Wood to Fletcher Building's 1,500 home development plans at the Three Kings quarry. Wood has campaigned with locals to stop the development and negotiate changes with Fletcher, but has said he expected to eventually see a better quality development completed with over 1,000 homes.

"You've heard about Labour's housing policies, but when it comes to actual developments, they're opposed to them," English told his post-cabinet news conference on Monday.

"While our opponents talk about a Kiwibuild policy, in practice they've actually got a 'no build' policy. That is, where developments are proposed in their communities, they are opposing them," he said.

"How you would ever get 100,000 houses built if you're against the Point England Enabling Bill and opposed to the Three Kings development is just ridiculous. There's no credibility in those undertakings to build lots of houses if you're opposed to actual houses getting built."

English's comments came after his Social Housing Minister Amy Adams announced the government planned to build a net 26,000 new homes in Auckland over the next decade, including at least 4,100 affordable homes, at a cost of over $2.2 billion.

Labour pounced on the Adams plan while English was overseas, accusing the government of an inadequate response to a crisis it was in denial about. Labour Leader Andrew Little said the government was planning to build just new 400 affordable houses per year for an Auckland population that was growing at 40,000 per year, while Labour planned to build 50,000 in Auckland over a decade.

English knows this is a potential weak point for the government and was quick to hit back.

A poll of 750 people by Ipsos for Chartered Accountants Australia and New Zealand found 22.7 percent of New Zealanders thought housing was the top issue that needed to be addressed in the Budget. Labour released results from polling firm UMR in May that showed housing was the biggest issue for voters in this election, followed by inequality, poverty, immigration and then the economy. Housing was only ranked fifth as an issue in the 2014 election and did not rank at all in 2008 and 2011.

English said the government's plans were based on what it knew was feasible from its experiences at Housing New Zealand's Hobsonville and Tamaki developments.

"Until you get all the details right, you don't have a single house. Our opponents have a concept they're talking about, but when it comes to actual houses they're actively opposing them," he said.

"There's no credibility in a policy if you can't say where they're going to be built, how you're going to pay for them, and more particularly, how you're going to get a council to make the decisions to allow the houses to be built, because governments don't make those decisions - councils make those decisions."

The clash intensified in Parliament on Tuesday with Little citing criticism of the government's "chaotic and shambolic" housing policy, and English responding by pointing to Labour's acknowledgement it would have to buy private land for Kiwibuild projects.

"I will tell you what is chaotic and shambolic," English said to a chorus of jeering from the opposition.

"It is promising to build 100,000 houses and then realising you do not have the land to build them on, it is promising to build 100,000 houses with no money, and it is promising to build 100,000 houses but opposing the actual building of actual houses in Point England and in the Three Kings development, where the Labour Party is the main obstacle to thousands of houses being built," he said.

Little followed up with this question: "If he wants a housing policy that will actually work, why does he not just take Labour's housing plan? He could lose himself in it, and we will not even sue him for copyright."

Where will they find the builders?

English also signalled a potential attack line against Labour in the election, saying it could not promise Kiwibuild while also cutting migration.

"If you have a policy that says you're going to build 100,000 houses, but you're opposed to any individual development, and you're going to shut down migration - cutting it by tens of thousands - there's no way you're going to be able to get the houses built. It's just dumb," English said.

English agreed that construction industry skills remained a constraint and he also declined to say the government would loosen settings to allow in more trades people to help with the Auckland build.

"Yes it's a constraint. That's one of the reasons we've defended having migration of skilled people, because we found from Christchurch that's how you got the houses built. If we hadn't allowed the migration of skilled people, you would have still rising house prices in Christchurch because of a shortage of supply," he said.

"Because we allowed migration of skilled people, the houses have been built and house prices in Christchurch are flat to falling. The Labour Party policy of shutting down migration completely contradicts their policy of building thousands of houses."

Asked if the government would loosen settings to allow in more trades people to Auckland, he said the current settings were about right.

Labour has yet to release its migration policy explaining how it would cut tens of thousands of migrants, although Housing Spokesman Phil Twyford has indicated the policy would prioritise builders over lower skilled migrants.

"We will choose the electricians, the plumbers and the carpenters instead of bringing people to this country to flip burgers and pump gas," he said.