BASIX sets water and greenhouse gas reduction targets relative to the average per person residential use of potable water and average greenhouse gas emissions in NSW prior to the introduction of BASIX.

What are the BASIX benchmarks?

• water: the average NSW annual potable water consumption from the residential sector on a per capita basis
• energy: the average NSW annual greenhouse gas emissions from the residential sector on a per capita basis.

How are the benchmarks determined?

The benchmarks are determined based on NSW consumption data collected from energy suppliers by the NSW Office of Environment and Heritage (formerly Department of Energy, Utilities and Sustainability).

• for water, the NSW benchmark is expressed in terms of potable water consumption and is equal to 90,340 litres of water per person per year.
• for energy, the NSW benchmark is expressed in terms of residential greenhouse gas emissions and is equal to 3,292 kg of CO2 per person per year.

By multiplying the water and energy per-capita benchmarks by average occupancy rates obtained from the Australian Bureau of Statistics for dwelling size and location, a water and greenhouse budget for a proposed dwelling can be calculated. Savings are calculated by comparing the dwelling’s modelled performance to this benchmark figure.

To obtain a BASIX Certificate, a minimum level of savings, expressed as a ‘target’, must be achieved.