Building New Zealand’s First Sizable Steel-Less Timber Building

By Rianna Lowrance, AEC Industry Writer

When Scion, a Crown research institute that specializes in the forestry industry, needed to upgrade its facility in Rotorua, New Zealand–dubbed the Scion Innovation Hub–it was interested in making it a place for interconnection and collaboration, as well as a beacon for sustainable design. 

The resulting building, designed by RTA Studio and Irvin Smith Architects, is the first sizable steel-less timber building in New Zealand, and reflects the Scion’s role in driving research, science, and technology for the forestry, wood product, wood-derived materials, and other biomaterial sectors. The building mainly consists of mass timber, a material known for being more sustainable and which ties back to the Scion’s mission of leading New Zealand towards achieving net-zero by 2050.

Updating the existing Scion campus and moving it into the 21st century was no easy feat. It took a confluence of factors to pull off, including a creative design team, innovative technology, a willing client, and the right cultural and environmental context. 

Using transparency to bring Scion’s work to the forefront 

Like a lot of 1960s architecture, the existing Scion building was closed off and didn’t facilitate collaboration. It was a big maze, with a number of office and lab spaces that were sporadically sprinkled across the building, creating physical chasms that hindered research collaboration and department connection.

In contrast, Scion wanted a new, modern workspace that could be used to promote research, encourage interconnection, and educate the public about its work, helping usher in a new era of transparency for an institution that works on New Zealand’s behalf. 

With transparency as the main design goal, Rich Naish, RTA Studio’s design director and the Scion building’s lead designer, developed a master plan that relocated the main entrance to the opposite end of the site, adjacent to the Whakarewarewa Forest Park entrance. This design choice raises awareness about the Scion’s work by making it more visible when people pass by, as they often do when visiting nearby hiking destinations. 

The designers then created a beautiful, centralized atrium on the building’s ground floor to help draw visitors in. This included a kaleidoscope of colors and repeating timber beams that inspired people to look up at the beautiful wood, as they might in a forest. 

The building layout was overhauled to create more visibility into the scientists’ workplaces, enabling the public to see them at work at any given time. An open layout also encouraged spontaneous interactions between the scientists, helping to foster open collaboration and public exchange, a perfect example of how purposeful design can positively influence people’s behavior.

Would a building made entirely of wood be possible? 

In addition to an open layout that enhanced the transparency of the Scion’s work, the design team also proposed that the building be made entirely of wood, which had never been done in New Zealand before. At first glance, engineer Alistair Cattanach said it was impossible. However, a week later, he presented a solution that mimicked how one would finger joint timber for furniture—only at a much larger scale. 

This was accomplished by joining two pieces of wood together with six to eight 100mm fingers, with the interlocking elements glued together—making the bond so strong that it creates one structural element out of two pieces of timber. Understanding how to engineer the joinery was the “eureka” moment that spurred the revolutionary construction technique applied throughout the timber structure. 

Luckily, Scion’s stakeholders are timber scientists who understand the unique properties of wood, and they knew that an all-wood structure was the way of the future—and, more importantly, possible. 

“Typically, mass timber buildings, particularly hybrid buildings, might have concrete floors on the upper levels. This places a lot of heavy mass above ground level that would require significant seismic restraint. At Scion, all the upper-level floors are mass timber, making them lighter and able to be restrained by the diagrid structure,” said Naish. 

The wood structure’s lightweight footprint and repetitive design elements cut design time and construction costs. That’s because there were only six different components for most of the structure–a diamond cut vertically, then in half, a diamond cut horizontally, and corner pieces. 

Having fewer components reduced manufacturing and construction waste since predictable shapes reduce leftover timber cuttings. With such simple building blocks, the team could purposefully specify all of the components beforehand, and allow for more accurate cost estimating as there was no need to factor in modifications or additional expenses.

Incorporating cultural values into the building design

Scion and the design team were also interested in incorporating the local Maori tribe’s cultural values into the building’s design to help minimize the impact on local surroundings, while also protecting and championing the spaces sacred to the Maori. 

The Maori view the forest as a sacred space that provides protection. With the tribe’s input, shades of green reminiscent of the diverse hues found in a tree’s leaves adorn the building’s glass envelope. 

“We often find architecture is like nature. A tree is just trying to hold its leaves off the ground, but it becomes the most beautiful-looking thing as it grows. When you come into the three-story atrium, all these divergent wood beams are holding up the structure like the limbs of a tree,” said Naish. 

Technology at play

Trimble’s SketchUp, a 3D modeling software, was used from the initial concept design through the preliminary design phase. SketchUp’s geometric modeling capabilities aligned perfectly with the repetitive timber components, facilitating rapid design iterations. “We use SketchUp because it’s quick and easy. We created groups and components, so changing one component could be easily reelected across the entire design,” said Naish. 

The model was shared with the client and the engineering team, and as the project advanced, Revit was used alongside SketchUp so that two parallel models could be built. While the Revit model contained intricate details, the SketchUp model was used for presenting milestones to the client since it simplifies iterative design improvements and enables designers to create compelling presentations.

The SketchUp model was frequently used to show the building’s scale and appearance without having to model as many details as is common with other software programs. This simplicity allowed them to save time and not promise color schemes or other specifics that needed to be changed later. When the team wanted to show more realistic details like material and shadow for project milestones, they used Enscape.

Once the design was modeled in 3D, the timber manufacturers imported the files into software that their CNC machines could read. The manufacturers made a virtual model of everything they would manufacture and ran it through digital processing before cutting any timber. This reduced rework and material waste. 

Components were then cut at the timber factory and shipped to the site in batches for specific building sections, further simplifying assembly on site. The building parameters went up within two days, the floors were installed in a week, and the second-story framing took another couple of days. Using timber and the new joinery system saved time during the build and won the team many accolades down the road. 

World-class design that will stand the test of time

After completion, the building was certified carbon neutral due to the significant amount of timber involved, which is a carbon-negative material. The building’s operating costs are also approximately half of those typically seen in a civic or commercial building.

The building’s success is a result of a design team committed to environmental, cultural and social responsibility, along with a client who believed in the importance of those considerations. Naish cautioned that, “It’s not just about striving for every potential green cost-saving measure. The client needs to share a commitment to building sustainability for the good of the planet.”

From the way it pays homage to the forest with a symbolic design that honors local people, to how it aligns with the facility’s mission, the cascading benefits of the design process were possible due to cutting-edge timber technology, carbon-neutral design and stunning aesthetics. 

“Many children will come in on school trips or with their families, and they just love to sit where the timber beams form a cradle. You see adults touching the wood, hanging out in the building like they might in a forest clearing. You don’t usually see this childlike behavior with adults–it’s been fantastic,” said Naish.