Hangar 4 is the new centrepiece of Air New Zealand’s aircraft maintenance base in Māngere.
Hangar 4 is the new centrepiece of Air New Zealand’s aircraft maintenance base in Māngere. It delivers a 98m clear-span, 35m-high hangar of around 10,500m², connected to a further 6,000m² of workshops and maintenance spaces, stitched into the existing hangar and apron environment. This is a demanding aviation setting, with strict operational requirements, live airside interfaces, and the need to support meticulous maintenance processes at scale.
The primary operational requirement was a large, unobstructed maintenance bay where aircraft, stands and ground equipment can move freely and maintenance can be set up without constraints. The long-span mass timber arch-truss structure achieves the clear span without internal columns, keeping the working zone clear for safe circulation and efficient day-to-day servicing. The arched form is well suited to hangar use, providing the height and volume needed for aircraft maintenance. Timber’s strength-to-weight efficiency made the arch-truss solution viable at this scale, delivering the required volume with less structural mass.
Timber was selected following a detailed comparison with a conventional steel option, and it was chosen for its environmental benefits, light weight, seismic flexibility, and resistance to corrosion in a coastal, salt-air context. Early engagement with timber suppliers also confirmed the solution was commercially viable.
The primary roof structure combines LVL top and bottom chords with CLT webs, with CLT timber purlins and LVL runners supporting the ETFE roof system. Fabrication was treated as part of the design. XLAM supplied 780m³ of CLT and 580m³ of LVL (including LVL sourced from Nelson Pine) and built a full-scale prototype purlin section to validate geometry, assembly and tolerances.
Each truss was designed as five pre-assembled pieces. CNC-routed jigs and 700mm-long fixings were used to achieve tolerances, and all 7,141 components were pre-assembled into the five sections and coated at XLAM’s Auckland facility with the Cutek CD-50 stabilising coating system to protect against moisture during construction.
On site, prefabricated 25-metre sections (each about 38 tonnes) simplified assembly and improved safety. The logistics programme included 3D-scanned transport routes and a nearly 860km multi-port journey, with specialist trailers and route modifications, to deliver components safely and predictably into a constrained airside environment.
The lighter timber structure reduced demand on foundations and supported a materially efficient structural solution in a building type that is typically steel dominated. The exposed timber arches lift the quality of the interior, giving the hangar a calmer, more legible working environment than a typical industrial shed. The structure is paired with a semi-translucent ETFE envelope that supports a bright and thermally insulated working environment, reducing reliance on artificial lighting and heating.
Because the primary structure was manufactured and pre-assembled as timber components off site, there was less cutting, rework and skip waste on the airside apron, contributing to the project’s reported diversion of 93% of construction waste from landfill.
