Westralia Square 2 (WS2) is the new office tower now complete in Perth. It’s a piece of workplace design notable on a number of different levels: as the very first timber hybrid office tower in the city, and indeed as the new home for master engineering firm Arup themselves. Arup is the anchor tenant, with the design having been completed in partnership with Hames Sharley. The project celebrates Indigenous culture and is even targeting the Living Building Challenge.

In recent years, mass timber has emerged as a serious new design option for large-scale buildings. In the context of climate crisis, it’s a new approach that potentially provides some meaningful solutions – in particular, the possibility of creating structurally sound large buildings without, or with greatly minimised reliance upon, concrete, steel and other largely damaging materials. Arup’s innovative design involves an embodied carbon saving of about 70 per cent compared to a concrete equivalent building.

If anyone can lend credibility to the use of a new approach to building and structure in general, surely it’s Arup. Indeed, one of the stated ambitions of this project is to inspire other actors across the built environment to take a leaf out of the same book.

Developed by GDI Property and currently leased at 90 per cent capacity, WS2 was recently opened by Deputy Premier, Hon Rita Saffioti. Arup’s WA leader, Lewis Macdonald, comments on the choice for its WA headquarters: “Not only is WS2 at the forefront of sustainable office building in WA, but it is a good example of how smart engineering has on-the-ground benefits. Our engineering solution of a timber hybrid structure enabled GDI to increase net lettable space on this site, which sits over a pre-existing underground carpark, while simultaneously delivering carbon savings. It really pushes back on myths around green premiums, and the idea that sustainable solutions don’t make economic sense.”

Macdonald explains further: “For Arup’s offices, the timber structure unlocks additional sustainable outcomes. We were able to significantly cut down on waste in the creation of the void at the centre of the offices, removing the timber floor slabs in sections and reusing them in the design of the stairs and platforms, meaning less waste sent off-site, and reducing the need for new materials in the process. And unlike concrete, the timber can continue to be reused and recirculated in the future.”

GDI CEO and Managing Director, Stephen Burns, adds that the success of the timber hybrid build centres the issue of sustainability: “GDI Property took the decision to develop WS2 as a timber hybrid building, a novel approach for buildings in the Perth CBD, as it delivers significant project benefits as well as a step-change in the embodied carbon results which is becoming more important for governments, industry and the broader community.”

Related: The timber Black & White Building

Burns continues: “As sustainability targets loom larger and emissions reporting requirements becomes a bigger feature for governments and businesses, there must be a growing focus on the emissions generated by their office spaces, not just operationally, but for embodied carbon. The timber hybrid construction meant we could use the existing engineering in place for the carpark underneath us, building higher and bigger than a standard concrete build. It also meant less mess, quicker build times and an embodied carbon saving of about 70 per cent compared to a concrete equivalent building. 

“WS2 stands head and shoulders above other buildings for the combination of its quality and environmental outcomes […] We believe the way we have delivered WS2 brings a step change approach to minimising embodied carbon in our built environment. We are especially pleased that both Arup and Built, who were both integral partners in the creation of WS2, have recognised the intelligence and impact of WS2 have chosen it to be their new Perth headquarters.”

At a smaller scale, other reused materials include salvaged task chairs, comms racks, joinery carcasses and timber for furniture. Meanwhile, the design avoids a ‘Red List’ of worst-in-class materials, chemicals, and elements, in-keeping with the Living Building Challenge.

Arup
arup.com

Hames Sharley
hamessharley.com.au

Read about Bates Smart’s design for the Australian Embassy in Washington DC