New Zealand’s timber hangar, the world’s first aircraft maintenance facility built from engineered wood, is making waves around the globe. Opened in September by Prime Minister Christopher Luxon—who first commissioned the project five years ago while serving as the airline’s CEO—Hangar 4 is the Southern Hemisphere’s largest free‑spanning timber arch and has been designed to last in one of the most demanding seismic regions on earth.
Using cross‑laminated timber and laminated veneer lumber sourced locally by XLAM and Nelson Pine, the massive arches—each with up to 12,500 screws in individual trusses—were prefabricated into 25‑metre sections at a local plant. “They were assembled on site and lifted into place using New Zealand’s largest crawler crane,” the airline said. “Each 38‑tonne truss was hoisted upright at an 85‑degree angle, then locked with hundreds of 250‑millimetre screws.”
Spanning nearly 100 metres, rising 35 metres high and covering 10,000 square metres, the Auckland hangar can accommodate a Boeing 787‑9 Dreamliner alongside two Airbus A320 or A321 jets. Above the timber arches, an ETFE roof serves as a canopy, flooding the interior with natural light and retaining heat, eliminating the need for a conventional heating system. Secured with 250,000 screws across 20 trusses, the seismic‑resilient arch can flex up to 300 millimetres under earthquake loads, absorbing shock rather than resisting it.
“I am immensely proud of all stakeholders involved with this project. The structure stands as a testament to innovative, creative thinking and exemplifies the versatility of wood as a construction material,” according to Tom Bruce-Jones, the owner of XLAM and Chair of the Hyne Group and the UK-based James Jones and Sons Group. “By embracing timber as a core material, we are not only delivering architectural excellence but championing sustainable construction practices.”
Wood Central understands that XLAM’s involvement in the project extended across design, the timber supply, logistics and on-site installation, using a procurement method known as Design for Manufacture and Assembly (DfMA). In total, more than 780 cubic metres of cross-laminated timber panels and 580 cubic metres of laminated veneer lumber beams were used on the project, and to validate the complex geometry, a full‑scale prototype purlin section was built, allowing the project team and client to see the precision and scale firsthand.
The scale of the project demanded careful planning.
Trusses were prefabricated in multiple sections to allow safe transport, with routes 3D‑scanned and specialist trailers engaged to move components nearly 860 kilometres from Nelson to Auckland. “The DfMA approach enabled us to adopt a highly structured, early‑manufacture and pre‑assembly process to ensure the project met programme constraints both onsite and across the wider supply chain,” said Keith Knox, XLAM’s General Manager.
Last month, NZ Strong project manager Jimmy Corric, the builder responsible for the project, said that timber and geometry do what they do best. Speaking at Timber Construct – Australia’s largest timber in construction conference, Strong said timber “can wobble about in the breeze— because it’s a seismic structure,” who joined with Patrick Thompson (Studio Pacific Architecture), engineer Chris Speed (Dunning Thornton) and fabricator Daniel Jones (Xlam) to discuss the project. “You either make these really rigid structures that constrain everything, or you have structures that move a little bit and allow things to give,” he said.
