It was never taken seriously as Auckland’s stadium of choice for the rugby world cup, but phoenix-like it rises to a new life – as six buildings that comprise the Carlaw Park Vision Apartment Precinct, two more buildings that will be its Commercial Precinct, and yet another building that will be its Hotel and Car park Precinct. We focus on the latter.
Erecting a steel column to the building's full height
Project Architect Brent Alexander of Warren & Mahoney says the concept was to give the edge of the steel-framed car park a live front onto Nichol’s Lane. Above the cafés at ground level, Quest Hotel will occupy the next two levels, while at the top there will be one level of six apartments – all constructed in concrete to achieve easier inter-tenancy separations.
The car park behind the apartments is seismically a separate building constructed with a steel frame. There were several reasons for this, the main one, according to Haydn & Rollett’s Kim Barrett, being the speed of the construction programme. “There is a huge demand for car parking in this part of the city. With 620 spaces, our building meets the demand from residents on site and can still provide parking for some 300 commuters. This created an economic incentive for a fast delivery, which a steel frame accommodated.”
Brian Dippie is Haydn & Rollett’s Senior Project Manager. He is experienced at taking advantage of the attributes of steel-framed car parks, and influenced the decision to build this one with a steel frame. “Columns delivered to site were erected immediately to the full height. With concrete we could never have gone straight to full column height and it would just have been too slow,” says Brian. His on site Project Manager is Richard Powell: “The design specified columns of 690UB140s with Steltech steel beams. These had a span of 11.5m, which obviated the need for adverse column positioning and optimised the number of car park spaces.”
By testing the difference in efficiency between a standard flat deck car park with localised ramping and a sloping ramped car park with no localised ramping, Haydn & Rollett were able to conclude that the latter gave more efficient utilisation of the floor space, averaging one car per 28m². The localised ramping option averaged one car per 32m². More car park spaces were therefore available from the sloping car park with no localised ramping, and while this could have been achieved in concrete, as Kim Barrett said: “It was just easier to do in steel.”
Grayson Engineering put all 600 tonnes of steel together in quick time. With the building at its full height, each pre-cast double tee infill, which spanned 17.5m and weighed 18 tonnes, was craned to the top level and lowered down through the steel frame.
Hamish Neville of Holmes Consulting Group said: “For once, we didn’t need to apply clever engineering. The design was driven by a cost effective solution that was like a kit of parts. I designed K-bracing for all four sides of the structure, which has two lift towers and stairwells. The balustrade coordination went well.
The stairwell at the front gate
“It was necessary to take into account that Carlaw Park is positioned at the base of the Domain, not very far from the old Auckland shoreline. Our car park sits over a flood storage basin. Rather than build below the water table, we built above it, surrounding the perimeter with retaining walls and putting down a gravel metal dressing at ground level. In the event of a 1 in 100 year flood, the water table would rise but dissipate down Grafton Valley.”
With community facilities that include a restaurant, café, bowling green and swimming pool, this gated apartment complex is designed for active senior living. Some say that the ghosts of Carlaw Park’s rugby league history approve.
