The ‘Street wall’ of Castlereagh Street is a lively arrangement of stratified building programs over time. One of these buildings is the subject site and is read as the beginning of the narrative.

The dominant form of the historical building is geometrical, detailed in rendered masonry. The base, pilasters, cornice, and parapet provide the formal façade of the existing building and in turn prompt the nature of the new addition above. This new building is adjunct to the formal composition of the existing historical facade.

A lightweight steel curtain wall provides a counterpoint to the base building. The material characteristics are glass and white painted steelwork is composed in horizontal bands. The generous floor to ceiling heights allow natural sunlight into the peripheral and internal offices. Hatches in the façade allow natural ventilation into the building at specific points.