Tauranga City councillors have voted for the tallest car parking building from the list of available options for the proposed Harington Street car park site.

At last week's city council meeting, the vote was for a nine storey car parking building, two storeys beyond what city council transportation staff believe is the maximum practical height.

There is a nine storey parking building in Manukau City councillors were told.

The Tauranga building will have an additional two basement levels.

Cost for the 11 storey project is estimated to cost $31.6 million.

The project has $20.19m allocated in the 2015-25 long term plan. The extra is expected to be updated through the 2018-28 long term plan process.

Staff concerns are that the top two levels may be unused because customers won't drive up that far. The staff recommendation was for two basement levels and seven above ground.

Councillor Max Mason says the too high argument doesn't work with driverless cars expected to become a major proportion of vehicle traffic within the next ten years of the parking building's 50 year design life.

'Has there been any thought given to driverless cars, you get out at the bottom and the car drives itself to the top,” says Max.

At seven levels the 575 carparks will cost $47,000 each to build, says Max. If they add two more floors at $4.5 million extra, then the cost per car park is $33,000.

'It seems like quite a bargain, I imagine it will never be cheaper,” says Max.

Councillor Larry Baldock asked about a future pedestrian bridge across Hamilton Street to the future civic heart buildings, but that option has not yet been pursued, because the civic heart buildings are not finalised.

'It doesn't require much to think about where it might bolt in,” says Larry.

Steve Morris says the 'eleven storey monster” will become a white elephant that the city council will not be able to on-sell.

'It will cost more, too much for small provincial city like Tauranga. It will be a white elephant for many years. I want to get them off the balance sheet rather than putting them on there.”

Gail McIntosh and Kelvin clout also spoke in favour of the taller option. Gail says looming building Act change will prevent the council from adding additional floors after a seven storey building is completed – and it makes more economic sense with the additional revenue.

Kelvin wants more electric vehicle charging points but says it a detail that can be added.

'I agree with councillor McIntosh, it's never going to be cheaper,” says Kelvin.

The nine storey parking building will be between seven storey Harington House and the 11 storey Kingsview apartments.

The council decision on the scope option allows for the preliminary design to be finalised. Detailed design can now commence with a view to begin construction in November 2017 and remain on target for completion of the Transport Hub in December 2018.