Engineered Timber Construction

Architectus is increasingly involved in the design of innovative engineered timber structures. As a proven means to reduce greenhouse gas emissions and increase carbon sequestration, the use of mass engineered timber has an array of benefits. These include increased construction efficiency and waste reduction through Design for Manufacture & Assembly (DfMA), reduced loads on foundations and improved occupancy wellbeing. We work with industry partners to develop these progressive timber structures as illustrated in the examples that follow.

The Pā
The University of Waikato / Te Whare Wānanga o Waikato

The Pā is a multi-purpose facility designed to transform the on-campus experience for the University and its community. Located on a prominent ridge, The Pā provides a welcoming new main entrance, student hub and University marae for the Hamilton-Kirikiriroa Campus that reflects the University’s unique character.

Integral to the design, and the expression of the generating idea, is a glue laminated timber structure that supports a folded butterfly roof. The exterior profile of the building and interior space is defined by a rhythm of glulam frames made up of 900mm deep x 180mm thick members.

The timber structure features glulam members on weathering lines as part of a double storey raking glazed facade, concealed structural connections at all junctions, extensive cantilevers with limited backspans and a number of complex junctions including a five-way cantilevered connection over the main double height internal space.

The glulam frame has been assembled and prefabricated by Timberlab using some of the longest single pieces of glulam ever manufactured in Aotearoa.
(Architectus in association with Jasmax, DesignTribe, Wraight & Associates)

Glulam timber structure supporting the folded butterfly roof

Axonometric of Glulam timber structure

Glulam beam lamination process (Timberlab)

Study model of The Pā entry and site construction photograph

Hub junction detail showing connection of multiple glulam rafters with concealed structural brackets

3D view of northern terrace and site progress of cantilevered roof rafters

Section drawing through northern terrace – timber-propped cantilevered rafters

Timber & Biomass Research Facility

This Research Facility is part of a wider project to drive innovation and growth from New Zealand’s forestry, wood product and wood-derived materials and other biomaterial sectors to create economic value and contribute to beneficial environmental and social outcomes for New Zealand.

The proposal is part of a long-term project to transform an existing campus into a modern high-tech research institute that supports the transition to a circular bioeconomy with a focus on interaction between science and industry. The proposition consists of two projects; a laboratory and workshop development, and a new Bio Pilot facility.

Across both projects a modular / extendable timber Cross Laminated Timber (CLT) structure provides a simple repeatable kit of parts for the primary structural elements enabling large span, highly connected research spaces with the potential to utilise locally sourced, sustainable resources. The CLT components have been designed for prefabrication off-site and targeted specifically at a local manufacturer. Optimisation to standard production sizes and thicknesses helps to drive cost competitiveness with alternative structural materials. Local procurement of these elements has transportation and local economic benefits.

Structurally, innovative connections between the CLT panels and the foundations allow for repair as part of the earthquake resistance of the building while off-site CNC fabrication ensures quality of the structural connections and dimensional accuracy.

The new build is designed to meet the International Living Future Institute’s Core Green Building Certification criteria (a simple framework of ten imperatives that a building must obtain to be considered a sustainable building) and features rainwater harvesting and stormwater treatment, extensive photovoltaics, biomass boilers, public realm improvements and landscaping together with a high-performance building envelope providing passive environmental control.

As well as embodying state-of-the-art research into timber structures the proposal explores the potential of building with sustainable biomass-derived products developed in collaboration with the researchers. Potential to educate and the ability to showcase and promote the facility’s research outcomes are key benefits of this collaborative approach.

Exploded axonometric demonstrating the modular / extendable CLT structure and sustainability features

Exploded axonometric

CLT structure using simple repeatable kit of parts

Highbury Triangle
Building B

Highbury Triangle is a multi-residential Kāinga Ora development, design predominantly for their senior cohort. Comprising five apartment buildings (Buildings A-E) ranging in height from six to eight storeys, the development offers a total of 236 apartments.

During the design process, the team used BRANZ’s Life Cycle Analysis tool, LCA Quick, to assess the benefits of timber construction in reducing embodied carbon. A construction estimate and programme review found that a change from traditional to timber construction would be both cost and programme neutral. Presented with this evidence, Kāinga Ora opted for one of the buildings, Building B, to be constructed from engineered timber.

Building B is arranged over six levels and contains 30 apartments along with community facilities and customer services for all residents. The project has been designed with a focus on environmental sustainability, reduced embodied and operating carbon, and cost-efficiency.

The building is modular with consistent grids and apartment layouts to help optimise the construction process and drive efficiencies in the design of prefabricated wall cladding panels and timber framed roof cassettes. Laminated veneer lumber (LVL) moment frames are organised on the northern and southern elevations to provide openings and access to balconies while CLT panels form the intertenancy walls providing fire separation and bracing. Floor slabs will be constructed from CLT panels with a floating timber floor system providing acoustic isolation. The structural timber frame and floor panels will be manufactured off-site to enable faster build time, less transport, and reduced wastage.

Building B Timber Structure Perspective

Pre-fabricated timber frames and slabs

Section details


AgResearch is a Government-owned Crown Research Institute (CRI) tasked with delivering leading agricultural science and innovation to benefit the wider Aotearoa economy. The organisation’s new headquarters and research centre consolidates a research/laboratory building and a workplace building on a new site to form part of the agricultural science precinct in Lincoln.

Driven by a client brief to reduce the carbon footprint of the buildings and use locally sourced materials where possible, a timber structure for the workplace building was developed with benefits analysed to reveal a reduction of 1538 tonnes CO2e of embodied energy in relation to a comparable steel and concrete structure.

Upon arrival, an extending timber canopy envelops and welcomes staff and visitors into the new building reflecting the organisation’s sustainability ethos. This innovative timber structure is expressed throughout the building, with a regular grid of LVL columns and 1000m deep beams, paired with prefabricated timber cassette floor systems and glulam roof members, providing a rhythm and expression of natural materials throughout.

Close collaboration between Architectus, structural engineers Beca, and contractors Naylor Love, with Timberlab, Xlam and Potius throughout the design and construction process saw the development of a structure which has been optimised for efficiency and buildability. This includes a central spine of cross laminated timber (CLT) rocking shear wall which provides earthquake resistance for the building and a showcase for innovative timber technology.

Section of workplace and laboratory wings

Physical model

Timber structure and natural ventilation features

Axonometric view of the timber structure

Building envelope sections