Supply the issue: Harcourts

The latest census data shows New Zealand's population has passed 4.24 million people. There were more than 200,000 more people recorded in the most recent census than in the census seven years before.

Harcourts chief executive Hayden Duncan said most of the growth was in Auckland and Christchurch, which was also where affordability was at its worst.

"Prices have only risen sharply in Auckland and Christchurch. Construction simply has not kept up with demand. We need the government to make the consent process easier and more attractive to developers to build in our two largest cities."

The Reserve Bank's LVR speed limits would not help the problem, he said.

"Our population is growing and we need more houses. Adjusting LVR restrictions and interest rates won't change that. It also impacts on parts of the country where the property market is not strong. Provincial New Zealand, Wellington, Dunedin and Hamilton do not have an issue with housing affordability... but things have got harder for people wanting to purchase in these areas."

He said the situation would only get worse when Auckland and Christchurch's population growth sped up again.