Councillor Martin Gallagher was worried that toddlers could run across the road bridging Garden Place and Civic Square and be hit by a passing car because there were no physical barriers between the road and the play area.
Project designer Garth Falconer said the concept was a "little bit edgy" but an exciting part of the City Heart upgrade, which included the $3.7 million work on Garden Place completed last year.
Councillor Maria Westphal and committee chairman Dave Macpherson, who had spent time researching the designs, said visual barriers were proven to be a more successful way of getting people to slow down than signs.
Mr Macpherson said the surrounding streets would all be signed as 30km/h and rather than being aroad the council was just allowingcars to drive through a pedestrian area.
Council chief executive Barry Harris said speed signs could always be added once the area opened.
The committee decided against discussing the final road layout for the east side of Ward St because members did not have enough information.
Auckland Council opened its first shared space in Derby St in April last year and positive results have prompted the development of four others in or near the central city.