loading . . . Sustainable aluminium demand stacked in Tiwai Point's favour After a decade of talk and planning, the past year has seen a new building begin to rise behind Parliament.
A new space to house around a quarter of Parliament’s 120 MPs was originally conceived in 2014 and approved by Cabinet in 2016. Plans were drawn up for a five-storey building which would be constructed behind Parliament House, then occupied by a parking lot.
After the 2017 election, the project was put on hold as part of the Labour-NZ First coalition agreement. Although most parties in Parliament had supported the new building, NZ First had always opposed it and secured a pause in coalition negotiations.
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Finally, following the 2020 election, which saw NZ First out of Parliament, the project was resurrected. It is now expected to be completed by early 2027. However, it underwent significant changes as part of that process, project director Dave Wills says.
Dave Wills. Photo: Marc Daalder
“We did a good project review at that point and that’s where three objectives were added to the project.”
Those were sustainability, resilience and co-design with local iwi. To understand how these objectives have been implemented into the new building, Newsroom sat down with a range of those involved in the project in mid-December and was also the first media to tour and photograph the building site.
It is the first of these new objectives that has prompted the largest revisions to the project. The building has essentially been redesigned from the ground up in pursuit of a Green Star 6 rating – equivalent to “world leadership” according to the Green Building Council.
The Green Star system provides buildings with scores across a range of environmental factors, from the carbon impact of actually constructing the building to its energy and water use once it is operational.
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Buildings are scored out of 100, with 75 credits needed to achieve the top rating of 6. The new building at the design stage has earned 90.2 credits. Its real-world progress against the operational water and energy use targets will be tracked for three years afterwards to ensure it keeps that score, says Karl Wakelin, sustainable buildings leader at Aurecon, the firm that designed the new building.
Overall, the building is expected to produce 89 percent less climate pollution over an estimated 60-year lifetime than a non-sustainable, industry standard comparator.
Some of those reductions can be achieved with a focus on energy efficiency, from better insulation to smaller windows to reduce heat loss. The building will also have solar panels, estimated to reduce peak power use by 52 percent, and is fully electric with the exception of backup diesel generators. The solar panels will complement those already on Parliament House, which on an average summer day generate enough electricity to power a home for two months.
However, structural changes to the building’s design were also needed to meet the reduction targets.
“The original design [from 2016] was concrete and steel and with the target of six stars, that was going to be very difficult to maintain that. That was when we had the reasonably early decision in the re-kickoff of the project to go to New Zealand-grown and -sourced mass timber, structural timber systems,” Wakelin says.
Mass timber, viewed from inside the new Parliament building. Photo: Marc Daalder
Instead of reinforced concrete and steel for the superstructure, the building is primarily made of gigantic frames of mass timber – thin layers of wood glued together. While relying more heavily on the timber leads to far less climate pollution in its production than concrete or steel, using it for the structure of a building in this way comes with its own complications.
For one, there is the size. Kerrin Manuel, construction director at contractor LT McGuinness, says the building firm engaged in extensive computer modelling and testing ahead of the start of the build.
The fundamental building block of the new structure is what Manuel calls an H-frame – two 13m-long laminated timber columns, 80cm thick, connected together with three massive timber beams. Each H-frame is three storeys high.
“It’s a significant weight. It grew over the design period from 15 tonnes to 18-and-a-half for one whole set of frame,” he explains.
“We developed a hinge plan to build them in situ. We proved it out in our yard first, built a one-to-one scale, made improvements out in the yard months ahead of when we needed it here, to ensure that it could be done safely.”
Four H-frames on the new Parliament building site. Photo: Marc Daalder
In the end, LT McGuinness constructed the H-frames with a hinge at the base, so they could be placed horizontally and then lifted vertically with a crane. Although the process is relatively novel – this is only the firm’s fourth or fifth mass timber build – it turns out to be much faster than putting up a concrete structure.
Pouring one concrete bay might take five or six weeks, from tying the steel, pouring the concrete and waiting for it to cure. LT McGuinness, meanwhile, has got the time for putting up two H-frames down to an hour and a half.
There are other changes that accompany the new materials as well. While a traditional building might be built floor-by-floor, the new Parliament construction has followed a staggered approach. First, one part of the building is put up from ground floor to the top, then the next, and so on. This reduces the amount of time the timber is exposed to the elements.
Manuel also points to the strict tolerances. In a concrete-and-steel structured building, measurements and placements could be off by as much as 10 to 15mm when structural elements are installed. With the timber, that has to be narrowed down to just 2mm.
That’s just the process of actually building it. Back in the design stage, using timber threw up a whole new set of considerations. Sounds between floors needed to be muffled to a greater degree than in a traditional building.
“You can imagine, if you’ve got a timber floor, it’s quite hard. People walking in high heels or whatever, that can quite easily transfer. So what we’ve ended up with is a multi-layered floor system – a raised floor and then we’ve got the [timber] floor underneath,” says Marcus Welby, Aurecon’s building operations leader and a member of the project team since the very start.
“That had a double benefit, because it meant we could also run all of the data and cabling in that cavity which gave us a whole lot of flexibility.”
This is extra important because another challenge of working with timber was space. The structural elements are much larger than in a concrete-and-steel building, reducing the internal space available. That prompted the team to get creative about flexible spaces.
The multi-layered floor, for example, allows for easy changes to the layout of power points in a room. The designers coupled that with an innovative system for internal walls or partitions, called X-frames, which can be moved around with almost no major works. Floors are arranged on a grid system and inserts running along every half-grid allow for partitions to be placed or removed.
An internal view of the X-frame wall, before the exterior has been added. Photo: Marc Daalder
“The demountable partitions actually plug in under the floor. If it’s got a TV and a couple of power outlets on that wall, the wall itself has a plug and it connects to a connector underneath. We don’t have to bring the electrician in,” says Wills, the project director.
Welby says the flexibility means the whole space can be converted over the course of a weekend, if the occupants of the space change. For example, partway through construction, it was decided that the National Crisis Management Centre would be placed on the second floor, due to the building’s seismic resilience. Few changes to the design were needed to incorporate an agency instead of MPs’ offices.
“You’ve got a building that needs to be incredibly flexible because of change of government, a three-year election cycle, someone might leave a party partway through a term. You put these partitions in but you don’t need to change the services – you don’t need to change sprinklers, you don’t need to change the mechanical, you don’t need to change the lighting, it just automatically adapts,” he says.
The system will save money by reducing the costs of rearranging spaces. It also reduces waste from such intensive processes. One of the conditions of Green Star 6 is that there are no new fit-outs to the building in its first decade – but the X-frames allow for the whole space to be changed without a formal fit-out.
X-Frame. Photo: Marc Daalder
Then there’s the resilience of the new building. To future-proof it against projections of worsening flood risk due to climate change, the designers made the decision to have no key electrical components in the basement.
It also has state-of-the-art seismic resilience, including base isolators and shock-absorbing viscous dampers. It will be connected to Parliament House via an an air bridge. Designing that, Wills says, was particularly tricky, because Parliament is also base isolated but with older technology that moves differently in a quake. The bridge needs to be able to stay attached to both buildings in a smaller event and break off the right way in a large tremor.
Resilience is more than just earthquakes and flooding, Welby says. There’s also the basic infrastructure which buildings rely on, but which may not be available in a crisis. That includes power (hence the diesel backup generators) and three waters.
In the basement of the new building are several gigantic tanks, each capable of holding around 55,000 litres of water (or close to double a Fonterra milk tanker’s volume). One holds rainwater, another the water for the sprinklers. A third takes in wastewater if the city is disconnected from the wastewater network.
A rainwater tank in the basement of the new building. Photo: Marc Daalder
“The building can operate completely independent, without any of the city services, for three days at full load,” Wills says.
If fewer people than usual are working in the building, it can run autonomously for a couple of weeks.
“That’s in the case Wellington really gets hammered,” he says.
“Even if we don’t talk seismic, but we talk, say, there’s a wastewater failure. We can probably run Parliament. We just direct everybody to go and use the toilets in the new building.”
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