Demand could push up house prices and rents in Auckland, but areas outside the main centres have an overhang of supply, the ANZ bank says.

ANZ said anecdotes and talk of a shortage of housing were widespread, and it felt it needed to respond, particularly in relation to a shortage potentially driving up property prices and another mini-boom.

Across the country there was no housing shortage, but in Auckland excess demand had persisted for the past few years and was intensifying, ANZ said.

Even assuming no depreciation of existing housing stock in Auckland, the number of consents issued had fallen short of household growth.

"In contrast, other parts of the country have been increasing their housing stock at a faster rate than growth in underlying demand."

That was particularly the case in areas outside the main centres, ANZ said.

With Auckland likely to be the main beneficiary of net migration inflows, excess demand there was likely to intensify in the coming year.

"This will lead to upward pressure on rents and house prices in the region, if housing supply does not start to respond soon," ANZ said.

But other parts of the country without any excess demand would continue to face downward pressure on house prices, particularly those in popular holiday home hotspots.

"If supply does not pick up in Auckland, we could well see a divergence in the performance of house prices around the country, particularly as the economy emerges from recession and begins the long road to recovery," ANZ said.

It acknowledged that building consents had collapsed to levels last seen in the 1960s, while net migration had accelerated, but said that came after several years of excess supply.

ANZ estimated 37,000 excess dwellings had been built since 1991, although there were some uncertainty regarding key assumptions.

Despite those uncertainties, a housing buffer existed that could be used to absorb any temporary excess demand.

Looking at the total number of households, versus the total number of dwellings in the country, suggested there were still enough vacant houses to satisfy several years' worth of new demand.