Sites of the Takapuna houses from last year's The Block renovation show are earmarked for buildings of at least four-storeys in the proposed Unitary Plan.
The four houses, at present in a low-rise suburban neighbourhood, are in Anzac St West where Auckland Council's new growth planning rule book aims to allow terraced houses and apartments nudging the future metropolitan town centre.
The plan's rules for higher-density housing do not have legal effect yet but owners of last season's TV3 show homes are studying them with an eye to boosting the value of their land.
"We were well aware before the auction [September 2012] of it being earmarked for future growth and thought that would be good for the future," said Lisa and Stewart Hampton, who paid $961,000 for their property and run their business from rooms fronting the arterial road.
"It will be a good spot, though I imagine it won't happen for a long time," said Lisa Hampton.
Neighbour Kristina Clements said she knew about provision for multi-storey development and, though interested, had not explored it.
For now the house suited the family of four's needs, being in close walking distance to schools.
She bought it for $789,000 and spent $30,000 on upgrading it.
A council spokesman said the plan allowed six storeys but had a required street frontage length for a development of five or more dwellings.
For a four-storey building, the requirement meant two properties would need to be amalgamated to give the width. Greater height was possible but the application for planning consent might have to be publicly notified. In July 2011, the houses had a land value of $570,000.
Barfoot & Thompson real estate business development manager Clinton Hardy said making money out of a site's promotion to a multi-storey building zone was not necessarily a sure thing. He said the financial viability would be affected by the cost of removing the existing buildings and rebuilding in multiple storeys.
The potential for profit might have been better if the four houses had been removed before renovation and the sections merged.
The council spokesman said an important stipulation in the North Shore District Plan was the effects of any buildings over four storeys on the Auburn Reserve, which is to the south of the Anzac St West properties.
One effect would be shading of Takapuna Croquet Club. This prompted an appeal against any high-rise allowed in the present plan, said club past-president Judy Hoquard.
"We appealed and went into mediation. The club's consent must be obtained in writing for a development of more than four storeys."