Ballarat GovHub will accommodate up to 1000 Victorian Government employees, including up to 600 new and relocated public sector positions. It will centralise the delivery of a range of government services, making it a one-stop-shop for customers and a hub for local activity. Development Victoria is leading the development of a new government office within the Civic Hall Site in partnership with Regional Development Victoria, the Department of Premier and Cabinet and City of Ballarat. This will complete a community, government and commercial precinct in the Ballarat CBD. As a key driver in revitalising a major part of the Ballarat CBD, the GovHub is a $100 million, 15,000m2 five-storey timber office building was completed by the Kane Constructions and Nicholson Construction joint venture in April 2021.
AECOM was engaged by Development Victoria for all engineering disciplines to design the first mass engineered timber commercial building undertaken by Development Victoria, and one of only a handful in the country. The brief was to thoroughly investigate all options to provide a template for future exemplar timber developments.
The architectural quality of the building, adoption of timber as a renewable structural framing material, and focus on sustainable and flexible workplaces, makes this project unique. AECOM undertook a thorough concept and scheme design process to explore a wide variety of options that were then narrowed via detailed comparison-scoring tables to communicate the pros and cons of each scheme. Key issues explored were the type of mass timber product, the size of the grid, constructability and the application of hybrid structural systems. A significant body of work was accumulated from these studies that helps clearly define the constraints, opportunities and viable configurations for a commercial timber office building.
The architectural design is unique and features a number of challenging elements that required creative engineering solutions. Timber does not as readily cater for large cantilevers and irregularity of vertical structural elements, and the scheme involves both. a 7m cantilever at one end of the building and a warping roof geometry. Both challenges were solved by investigating steel-timber hybrid solutions to ensure that the building could achieve the required high architectural quality on budget. The hybrid solutions also maximised buildability, while mitigating statutory approval and programme risk. This approach has been validated through the construction process and highlights the benefits around being pragmatic and sensitive to timber as a material in the design approach whilst maintaining a holistic view of the overall engineering solution.
A number of other challenges for the project include being on a contaminated site, the footprint being constructed on a flood plain and requiring demolition and seismic assessment of the adjacent Civil Hall Building.
Early 3D Coordination
The coordination of the structural frame to readily facilitate mechanical service distribution across a long thin floorplate was vital to minimising floor to floor heights and maintaining long-term flexibility of the building. This investigation of options was driven by an AECOM multidisciplinary approach, using Sketchup 3D and Revit modelling from project inception, providing rendered images of the spatially coordinated options for review by the wider design team and Client as the schemes were progressed.
Mechanical, acoustic, fire and structural engineers inputted into the process to provide options that satisfied the requirements of each discipline. This digital modelling was integrated into the engineering scheme development to optimise the commercial building solution.
Commitment to Timber
The difficulty in getting accurate cost information prior to getting specialist timber contractor engagement is a significant challenge to the selection of timber as a structural material.
AECOM invested significant time soliciting preliminary input from both local and international specialist timber suppliers in order to demonstrate technical and cost feasibility of the scheme. However, without a specialist timber contractor on board AECOM proposed running two structural schemes to tender in order to allow the market to test the timber alternative. This proved decisive in realising timber as the final structural material, creating the unique and ground-breaking project that was requested in the brief.
As part of our commitment to timber, AECOM’s acoustic team have undertaken detailed footfall vibration measurements at various stages of the construction process to accumulate a body of data for use on future projects
Hands on Coordination with Timber Contractor
AECOM were responsible for certifying the timber design and worked extremely closely with XLAM Dolomite as the specialist Timber Contractor throughout the construction phase. AECOM defined and engineered the most complex parameters such as progressive collapse, fire engineering solutions and diaphragm and vibration performance. The hybrid nature of the scheme also meant there were many interfaces with steel and concrete elements that AECOM had to resolve. Workshops were held with the timber contractor 1-2 times a week throughout the construction documentation period to ensure a locally compliant, coordinated and efficient design was developed.
AECOM’s fire engineering team worked through a challenging statutory approval process at a time of increased scrutiny on fire engineering solutions for mass timber construction in the Australian market and attained the required approvals.
Architect: John Wardle Architects