Skyhaus, 420 Macquarie Steet

Located in Liverpool, one of the key satellite suburbs of Sydney, 420 Macquarie Street is currently the tallest residential development in the area. The residential complex comprises two 32 storeys towers plus a sister tower at six storeys. The buildings include retail spaces on the lower levels and swimming pool located on a shared roof space. The complex will usher in a new generation of high-end living into Liverpool, and inject more life into the already vibrant community.

A very high degree of fire engineering and structural fire engineering principles were applied to the building. One of the unique input Holmes  brought to the project was the reduced flat slabs that were demonstrated to achieve the required fire resistance levels throughout the building. This performance solution resulted in considerate savings to the project including approximately 1600m3 of concrete and 4000 tonnes of concrete. This not only improved the constructability of the project, but significant benefits were realised such as improved cost-efficiency and simpler construction techniques, while also improving the occupational performance of the complex over the lifetime of the structure.

Despite the significant benefits this provided in reduction to construction resourcing costs and timeframes, notable flow-on benefits of the thinned slabs was the design flexibility for the project. Standardised façade systems were catered for without increasing the overall inter-storey height of the building, and slab set-downs in wet areas were also not required, resulting in further cost savings to the project. Subsequently, the considerable benefits to this project has led to this structural fire engineering analysis to be conducted on a multitude of reinforced concrete projects, with dozens completed to date.