The base building achieved a 5 star NABERS Energy Rating in July 2019. Also a 6 star NABERS Indoor Evironment Rating July 2019.

The NABERS Energy rating scheme promotes low-energy consumption through highly efficient air conditioning, lighting and lift control systems. The double-glazed facade and special window design control heat loads and encourage natural light to penetrate the workplace.

The high ratings for both NABERS Energy are achieved by incorporating the following key components;  

  • Low energy demand through use of low energy consuming systems, including a Variable Air Volume air conditioning system incorporating economiser cycles, night purge, optimised scheduling, efficient chilled water vessels and high efficiency Variable Speed Drives.
  • Efficient T5 office lighting, automatic light level control, multiple zone switching and motion detection.
  • High standards in Indoor Environment Quality
  • Minimum 3A rated water fixtures and fittings used throughout


The building at 181 William Street incorporates “Premium Grade” services via the latest technology including destination lift controls, high performance glazing, solar domestic hot water preheat panels and other features to achieve high ESD ratings and reduced operating costs.