The original cathedral was constructed in two stages, the first in 1865 and the second in 1930. In 2006, the heritage building was redeveloped, which included renovating the existing building, as well as constructing major additions, above and below ground.

BG&E provided structural engineering for the $35.2 million redevelopment, encompassing a multi-functional basement level and a new ground level assembly area. The basement works comprised in-situ, reinforced concrete framing, and the new assembly area included the mixed use of structural steelwork and precast concrete. A significant amount of the structure was precast.

The part demolition of the existing cathedral required the use of complex, permanent retention systems for the existing foundation and wall elements.

Located in centre of Victoria Square in Perth, St Mary’s Cathedral’s new curved design and second spire ensures the building remains a hallmark of architectural elegance.