Proposed changes to BASIX targets

14 February 2014 | By Louise Camenzuli (Partner)

In December 2013, the NSW Government announced proposed changes to Building Sustainability Index (BASIX) targets. These changes represent an average additional 10% reduction in water and energy consumption for houses and residential apartments. In setting and implementing these targets, the challenge for the NSW Government will be to effectively promote increased sustainability measures whilst minimising implementation costs to industry and households. Submissions are invited on the proposed changes and close on 14 February 2014


BASIX is a planning tool for residential dwellings to increase overall building sustainability.  BASIX certificates must accompany all NSW Development Applications for residential dwellings, including multi-unit residential developments and alterations or additions costing over $50,000.

Introduced in 2004, BASIX sets targets for water consumption, energy consumption and thermal comfort.  These targets are calculated with reference to existing dwellings of similar type and location.  They are expressed as percentage savings from the average benchmark (ie. the state-wide average per person water consumption and greenhouse gas emission levels).  Under current BASIX targets, most residential developments must be designed to reduce mains water use and energy consumption by 40% against the average.

The proposed changes to BASIX follow from the 2011 BASIX 5 Year Outcomes Review, a 2011 cost-benefit analysis conducted by Allen Consulting Group, and consultation with stakeholders.

Proposed changes

The changes to the targets are:

  1. intended to keep them in line with national standards;
  2. reflect the advances in sustainable technologies and industry best practice; and
  3. ‘future-proof’ houses against changing weather conditions and increases in utility costs.

Like the current BASIX targets, the proposed new targets are specific to the type of dwelling.  They will also continue to take account of regional variations, and will retain flexible compliance options to allow for a range of measures to be implemented in order to meet BASIX targets:

  • For detached houses, attached houses and low-rise buildings, existing targets will be increased to achieve an additional 10% saving in water and energy consumption.
  • For mid-rise buildings, existing targets will be increased to achieve an additional 5% saving in water and energy consumption.
  • For high-rise buildings, existing water consumption targets will remain the same, while energy targets will be increased to achieve a 5% reduction in energy consumption.
  • Thermal comfort targets will be increased.  Caps for heating and cooling will now achieve 5.5-6 out of a possible 10 stars under the Nationwide House Energy Rating Scheme, up from the current 4.5-5 stars.

Costs of compliance

Compliance costs for the proposed BASIX targets are estimated to increase, compared with current compliance costs.  These costs will initially be borne by developers and industry, and are expected to be passed through to purchasers.  This will result in an estimated increase to house and unit prices by an average of 0.7%.[1]  However, the Government claims that for households, the new targets will result in an ‘overall improvement in housing affordability’ due to the expected reduction in utility expenditure.  Increased costs for industry have therefore been justified on the grounds of benefit to the NSW economy as a whole, with the 2013 Allen Consulting Group benefit-cost analysis concluding that every $1 spent on additional compliance measures will benefit the NSW economy by $1.64.[2]

To ensure development that already complies with the BASIX 40 target meets the revised BASIX 50 target, reports estimate that it will cost, for example:

  • an extra $4,069 in design and construction costs for an average single detached dwelling, and
  • an extra $1,216.15 in design and construction costs per unit in a 13 unit low rise development.[3]

As with the estimated benefits, the estimated costs vary greatly between dwelling type and can potentially be reduced by incorporating particular design features, for example, installing fans and glazing instead of air conditioning.

The detailed benefit-cost analysis undertaken by The Allen Consulting Group is available here.

How will the changes be implemented?

If the proposed changes are approved, the Government has indicated that sufficient lead time will be given before the new targets take effect.  There is no indication of that timeframe, although industry stakeholders have called for at least six months.

There are also presently no firm details of the transitional arrangements, but the Government has indicated that development applications which have already obtained council approval will not be affected by the proposed changes, provided that the development is not substantially modified prior to completion.

For development applications that have not yet been submitted, there will be a window between announcement of the changes and implementation of the new targets, to allow developers to submit a pending application under the current BASIX targets.

Upon finalisation of the review and submission period, clarification will be needed from the Government on these transitional arrangements to ensure compliance.

Potential for future changes

The current review is confined to BASIX targets and ancillary policy changes, though there have been wider calls for changes to the overall scope and procedure of BASIX.  Some aspects of BASIX which may come under review in the future include:

  • the stage of the design process at which assessment occurs;[4]
  • the key factors assessed in BASIX targets such as the need for greater examination of building materials;[5]
  • whether BASIX should extend to commercial buildings;
  • whether BASIX should place greater emphasis on results-based monitoring rather than the measures adopted;[6]
  • whether BASIX should include incentives to exceed the minimum targets set by BASIX.[7] Currently, the BASIX regulations[8] prevent any other planning instrument from imposing different standards on water, energy and thermal performance in housing, and there is no reward for achieving greater reductions in water and energy consumption.

For further information, visit the BASIX Target Review website here.

  [1] The Allen Consulting Group, Benefit-cost analysis of proposed BASIX stringency changes, pxi.

  [2] Ibid.

  [3] Ibid, p18.

  [4] A.Thorpe and K. Graham (2009) Green buildings - are codes, standards and targets sufficient drivers of sustainability in New South Wales? (2009) 26 EPLJ 486 at 490.

  [5] Ibid.

  [6] Ibid.

  [7] Suggested as a way to encourage best practice in Building professionals’ and homeowners’ perceptions of the NSW Building Sustainability Index (BASIX) - an overview at p. 5, available here.

  [8]State Environmental Planning Policy (Building Sustainability Index: BASIX) 2004 (NSW), r 7.

The content of this publication is for reference purposes only. It is current at the date of publication. This content does not constitute legal advice and should not be relied upon as such. Legal advice about your specific circumstances should always be obtained before taking any action based on this publication.

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Louise Camenzuli

Partner. Sydney
+61 2 9210 6621