Housing New Zealand would not disclose details about the property address, citing privacy reasons.

University of Auckland school of architecture and planning lecturer Bill McKay said it was probably an original 1940s state house in Auckland's eastern suburbs with either a family or pensioner living there.

McKay co-produced 2014 Beyond the State: NZ State Houses from Modest to Modern, which extensively covers New Zealand's social housing history.

Housing New Zealand should demolish single dwellings on high value land and replace them with medium density housing that could house about a dozen Housing New Zealand families, he said.

"I don't think they should be ripped out of the community. I think these people should be put back into redeveloped sites."

Too often Housing New Zealand land was to private developers, he said.

"There's this kind of belief that Housing New Zealand tenants shouldn't live in nice places."

Rather than selling land, Housing New Zealand should be developing sites to include a range of affordable and state housing, he said.

"With our housing crisis we've got to make efficient use of our land but we should maintain diverse communities with a variety of people in there.

"I don't think they should sell off any of their land to private entities."

In 2016 Housing New Zealand transferred stock to Tāmaki Regeneration Company (TRC), which plans to replace 2800 state homes with 7500 new homes over the next 15 years, some of which will be affordable housing. TRC is jointly owned by the Government and Auckland Council.

Housing New Zealand's 1940s houses were cold, and damp and needed to be replaced with new, warm, dry housing, McKay said.

Housing New Zealand uses independent valuers to assess the value of its assets.

The total value of all Housing New Zealand dwelling properties in Auckland is $16 billion, of which $12 billion is the land value.

The Labour Party campaigned on no sale of state houses, while the previous National Government did sell state houses and formed partnerships with private entities as well as local government.

The National Party's housing and social housing spokesperson Michael Woodhouse said the previous Government had a more pragmatic approach to housing.

"We championed on freeing up more Crown land so we could build more affordable and social houses."

Minister for Housing Phil Twyford needed to be more clear on what the Government's no sale of state homes policy was, Woodhouse said.

"Housing New Zealand need to extract the best value out of that very large tax payer asset," Woodhouse said.

Twyford did not respond to requests for comment.

The number of Housing New Zealand dwellings built each year in Auckland has increased from 37 in the 2013 financial year to 182 in the 2017 financial year.

Meanwhile demolition of Housing New Zealand dwellings increased from 69 in the 2013 financial year to 369 in the 2017 financial year.

As at October 31 there are 776 state houses and 124 emergency houses under construction in Auckland and 464 state houses and nine emergency houses contracted with construction yet to start.

Housing New Zealand has also lodged 90 projects for resource consent, which could result in 2276 new dwellings being built, if consent is granted.

Its total managed housing stock in Auckland has decreased over the past five years from about 30,800 to about 28,000, partly due to the transfer of property to TRC.