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The Arrow project team recycled much of the native timber from the original building for use in the new facility

Complexity no barrier for Arrow International in new Xero Wellington office

A heritage-listed building in downtown Wellington has been reconstructed for the digital age – fitting when you consider that the companies involved are ground-breakers in their own field.

The building has just become the new Wellington HQ for Xero, the global made-in-New-Zealand small business platform success story, after a major build helmed by Arrow International, which is leading some of the country’s most technically complex construction projects.

Arrow’s successful bid earned it the project and a high-wire juggling act that began in late 2015 and concluded with occupancy by Xero, the building’s sole tenant, in October last year. Xero’s primary objective was to house more than 600 Wellington staff on one site. More than that, the company wanted to make optimal use of the 6000 sq m footprint on a full city block on the corner of Taranaki and Wakefield Streets.

Bringing people together

Project director Robb Noble says the Arrow team called it ‘the Google office’ because of the espresso coffee stations, pool tables and bikes scattered throughout the building.

“Because the staff were to be spread over five floors and the point of the construction was to bring people together, Xero wanted to make sure people didn’t feel isolated. We put in a large central staircase with a full-height stairwell and a skylight. This floods the building with natural light and connects everyone in the building – they can run up and down the staircase and don’t even need to use the lift,” he says.

“The building has a large footprint compressed into five floors, which is unusual and largely a factor of the location. You couldn’t get that on Lambton Quay, for instance – you’d need a lot more floors for the same area – so location-wise the building is a real banger.”

The building is framed in steel and clad in aluminium and a transparent skin called Stamisol, which allows in natural light, but offers sun protection and a practical assist to the building’s air-conditioning system.

Complex and technical

Arrow’s CEO Ken Forrest says the combination of a heritage building – the original two-storey structure went up in the 1920s and was home to Manthel Motors and used as a World War Two storehouse before being converted to offices in 1990 – and a challenging site meant Robb and his team had to call on all their skills.

A large central staircase with a full-height stairwell and skylight floods the interior with natural light and connects everyone in the building

“The initial brief was to retain the first two levels and add another three, but once the work began it was clear that a whole new structure was needed. The team retained the two-level heritage facade on the outside and constructed five brand-new storeys within, with a new facade for the top three. The heritage facade is pinned to the new structure, which has been built for earthquakes to 100% of the new building standard,” he explains.

“It was a highly complex and technical job, even by Wellington standards, and the team really outdid itself in coming up with solutions to a variety of challenges that emerged once the work unfolded and the original building began to reveal itself.”

Embracing complexity

Though the build wasn’t straightforward, Robb says his team embraced the complexity of the brief. “We won the tender because we backed ourselves to do it – we knew we had the skill-set to think and work laterally. For instance, we needed a tower crane, but the building itself took up the whole block, so we put the crane inside the site where the atrium is and plucked it out after we finished putting the roof on,” he notes.

“To accommodate the construction we needed access to the street, but we had a state highway on one side and trolley bus wires running above the other – so we worked out how to make a gap in the wires without interrupting transport,” he adds

“Then there was the ground itself. To create an earthquake-ready foundation on this site we needed to use what we call jet piles, where an anchor is inserted deep into the subsoil – up to 25 m below ground – and then a deep soil-mixing technique is applied, which combines a highly tensile threaded steel bar with grout and the surrounding soil. We did a lot of the enabling work for the foundation and then used a specialist company for this aspect.”

Protective skin

Robb notes the Stamisol is a remarkable feature. “It’s a transparent skin wrapped around the building, and when you look at it from outside in the daytime it is a dominant dark feature, but when you’re inside the building you hardly see it. It lets in natural light, but you have all the protective factors.”

With the building’s age came a lot of native timber, and the Arrow project team, with both conservation and aesthetics in mind, took the initiative of recycling much of the timber into the new building.

Arrow worked alongside architects at Inside Design and engineering firm ISPS on the Xero project. Ken has been with Arrow since 2001. Robb joined in 2010 and has been involved the company’s increasing dominance of the Wellington apartment market. Arrow has several major projects in the central city, including a new $60 million apartment building at 111 Dixon Street.

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