Project Description
The St Marys Integrated Project Office (IPO) is a temporary 200-workstation design office created to support Sydney Metro for the design and construction of six new metro stations connecting St Marys railway station to the future Western Sydney Aerotropolis. Serving as a hub for the project teams, the IPO will facilitate effective collaboration in the construction of Critical State Significant Infrastructure (CSSI). The overall characteristics of the building consisted of a facade featured glazed curtain wall, four commercial levels, an outdoor terrace, internal access stairs and a lift.
Project Challenges
Robert Bird Group was engaged by Built on behalf of Sydney Metro, with our role encompassing the structural design of the building, including detailed design of foundations, a hybrid structural steel frame and cross-laminated timber (CLT) floor panels. Further to the structural design, we provided construction engineering services which included construction build sequencing and traditional temporary works.
A key challenge in this project was designing the structure to enable efficient construction and meet the accelerated timeline. In addition to optimising for construction efficiency, we had to account for the future dismantling and relocation of the building to accommodate future metro projects.
Added Value
We added value to the project through early involvement, allowing the building grids to be aligned with stock lengths of structural steel members, minimising wastage. Further value came from ensuring consistency in the structural steel framing across all levels, which sped up construction and facilitated future relocation of the building. This approach ensured the structure could be easily dismantled and reassembled for future metro projects. A testament to the simplicity of the design, including the structural steel framing and CLT floor panels, was the completion of the building structure in under 25 business days.
Sustainable Methodologies and Outcomes
Sustainability was a key consideration in the design of the IPO. Our structural framing was ingeniously designed for disassembly and reassembly, allowing the building to be reused for future metro project offices instead of constructing new facilities. The design brief required a 50-year lifespan, assuming reassembly every 10 years. To facilitate easy relocation, we standardised floor beams, column sizes, connections, and CLT floor panels throughout the building. Additionally, the lift core was fabricated and erected as a single piece, minimising erection time and simplifying construction by reducing loose members.
This approach not only reduced material wastage but also demonstrated how temporary structures can be designed with long-term sustainability in mind. The cradle-to-gate carbon (Modules A1-A3) of the superstructure was measured at 563 TCO2-e. Over five lifecycles, this design saved 2,534 TCO2-e compared to using standard single-use temporary like-for-like structures using prime materials.
By carefully aligning the building design with stock steel lengths, we achieved an 11% reduction in overall steel tonnage, which equated to a 33.5 TCO2-e reduction in the cradle-to-gate carbon footprint. We worked effortlessly with Built to ensure the most economical structural scheme was developed from the outset, focusing on minimising temporary works and material wastage and maximising efficiency.
Typically, project site offices consist of a series of demountable buildings and/or double-stacked shipping containers placed within a site compound. This IPO is the first of its kind, providing a fully integrated project office that can be dismantled from one project and reassembled at another, retaining all the key elements of a commercial building and significantly enhancing the built environment where project teams work and collaborate.
The IPO achieves several improvements to the built environment compared to a typical temporary project office, including:
- A more comfortable work environment for project teams relative to demountable building and shipping containers.
- Designated meeting spaces contained within a single building where project teams can collaborate.
- Comfortable site amenities for site personnel.
- A façade system with a glazed curtain wall that allows natural light to enter the building, unlike typical demountable buildings and shipping containers, which have minimal windows.
- Enhanced insulation, windows, doors, and roofing that minimise heat transfer, maintain indoor temperature stability, and further reduce energy consumption.