BASIX targets form part of the NSW planning system and are used to measure the environmental performance of residential developments across New South Wales.

The targets are designed to improve:

water efficiency
energy performance
thermal comfort
long-term residential sustainability

BASIX targets apply to many residential developments, including new homes, alterations and additions, duplexes and multi-dwelling projects.

Understanding how these targets operate early in the design process can help support smoother approvals, reduce redesigns and improve overall building performance outcomes.

What Are BASIX Targets?

BASIX targets are performance requirements established under the NSW Building Sustainability Index (BASIX).

The targets are used to assess whether a proposed residential development achieves the required sustainability outcomes before approval can be issued through the NSW planning system.

Rather than focusing on a single building element, BASIX evaluates how the entire home performs as a system.

This may include consideration of:

glazing performance
insulation
orientation
shading
ventilation
hot water systems
lighting
water-saving fixtures
appliance efficiency

The required targets can vary depending on:

climate zone
dwelling type
project scale
building design
development pathway

Water Reduction Targets

Water targets are intended to reduce potable water consumption across residential developments in NSW.

The BASIX assessment may consider:

rainwater harvesting
WELS-rated fixtures
efficient plumbing systems
landscape water use
hot water systems
appliance efficiency

Different NSW climate zones can influence the required water reduction targets and compliance pathways.

In many projects, early planning around rainwater systems and water-efficient fixtures can significantly improve BASIX outcomes.

Energy Reduction Targets

Energy targets assess the projected energy performance of the proposed residential development.

This can include analysis of:

glazing systems
insulation
lighting efficiency
hot water systems
appliance performance
building fabric
passive solar design

Good orientation, shading and building envelope design can often improve BASIX performance without relying solely on additional mechanical systems or high-specification products.

Early-stage design decisions frequently have the greatest influence on long-term energy efficiency outcomes.

Thermal Comfort Targets

Thermal comfort forms a major component of BASIX compliance in NSW.

The assessment evaluates how effectively the home maintains comfortable indoor temperatures throughout different seasons and climate conditions.

Factors influencing thermal comfort targets may include:

orientation
glazing performance
solar heat gain
insulation
ventilation
shading
thermal mass
building materials

For many residential developments, thermal comfort compliance is assessed using NatHERS modelling software.

NatHERS provides a more detailed analysis of how the building is expected to perform under different environmental conditions.

How BASIX Targets Are Calculated

BASIX targets are calculated using assessment tools that compare the proposed residential development against NSW sustainability requirements.

The assessment process may analyse:

building orientation
window size and performance
insulation levels
appliance efficiency
water systems
climate data
dwelling size
construction materials

The interaction between these elements influences whether the project achieves the required BASIX outcomes.

Because each project is different, BASIX targets are not applied as a fixed checklist and often require project-specific adjustments during the design process.

Factors That Affect BASIX Performance

Several factors can significantly influence BASIX target outcomes, including:

excessive west-facing glazing
insufficient shading
poor orientation
limited insulation
inefficient hot water systems
late-stage design changes
minimal passive solar consideration

Addressing these issues earlier in the design phase can often improve compliance efficiency and reduce unnecessary redesigns.

BASIX Targets and Building Design

BASIX performance is closely connected to overall building design.

Well-considered passive design strategies can often improve:

thermal comfort
energy efficiency
indoor comfort
long-term operational performance

This may involve coordination between:

architectural design
glazing selection
thermal performance modelling
insulation systems
planning documentation

Integrating these considerations early in the project can support smoother approvals and stronger long-term building outcomes.

BASIX Targets and NatHERS

BASIX and NatHERS are closely linked for many residential developments in NSW.

While BASIX establishes the broader sustainability framework, NatHERS modelling is commonly used to assess thermal comfort performance.

NatHERS can provide greater flexibility when balancing:

glazing performance
insulation
shading
orientation
thermal comfort outcomes

This can often support more cost-effective and better-performing residential designs.

Frequently Asked Questions