Does the NCC need to be updated to deliver more resilient buildings?

10 April 2014 — The Australian Building Codes Board is seeking comment on whether changes to the National Construction Code are necessary to deliver buildings with better resilience, as increased numbers of extreme weather events and shifting weather patterns begin to threaten the built environment.

A discussion paper, Resilience of Buildings to Extreme Weather Events, has been released to outline the key issues and promote input from stakeholders. The feedback will be used to inform advice the ABCB provides to governments in relation to potential improvements to national and state codes and legislative requirements for buildings and plumbing systems.

The ABCB statement released with the discussion paper states “new buildings are currently designed and constructed in accordance with the National Construction Code (NCC) to withstand climate related hazards such as cyclones and extreme winds, intense rain, bushfire, snow and flood, as appropriate to their location”.

The NCC does not, however, cover hail, storm tide or have specific requirements relating to heat stress. It is therefore appropriate for the ABCB to seek feedback and consider whether these other hazards can be addressed in the NCC.”

Climate change is very much at the centre of the discussion. The paper’s introduction points out that the Council of Australian Government National Adaptation Framework, the 2011 COAG National Strategy for Disaster Resilience, as well as the Productivity Commission Report into Barriers to Effective Climate Change Adaptation all recommended that the ABCB should “continually monitor climate related hazards and review the NCC to ensure the standards are appropriate for the risk environment, taking climate change into account”.

The ABCB held a Climate Change Adaptation roundtable in Melbourne on 17 April 2013 to assist the Board to further develop a strategy for improving the resilience of buildings and plumbing systems in the face of extreme weather events and a changing climate. Considerations included natural hazards, energy, water and material use.

Fourteen high level external stakeholders from industry, research institutions and government also attended to inform the discussion. The roundtable outcomes were used to inform the discussion paper.

The principal impediments to amending the NCC to achieve better climate change adaption identified by the roundtable participants included lack of robust data, lack of government and community support and affordability.

Some of the key points raised in the discussion paper include:

  • In December 2010, the ABCB Office completed a report titled An Investigation of Possible Building Code of Australia Adaptation Measures for Climate Change. The purpose of the report was to identify and review the potential impacts of climate change on the BCA to contribute to strategic policy development by the ABCB. The report identified there is a reasonable level of confidence that new buildings constructed to the BCA can withstand current climate hazard design events (noting that a building withstanding all types of events can be guaranteed and that maintenance is a critical factor), and will cope reasonably well with future events that are slightly more severe under a low emissions scenario. The largest concern is in relation to existing buildings constructed prior to today’s contemporary building standards. These buildings are likely to be vulnerable to current climate hazard events, so would be even more vulnerable when faced with the prospect of more severe future events.
  • Under a high emissions scenario, the need for buildings to be more resilient to the impacts of climate change becomes more critical because climate related events have the potential to be more extreme. For example, heat stress may become a critical factor impacting on public health and wellbeing, which could necessitate significant improvements in building passive design and ventilation.
  • The ABCB is not a climate expert. The ABCB must rely on policy makers and climate/weather experts to provide advice and robust, consistent research and evidence as to whether and to what extent climate changes are affecting extreme natural hazards and should be taken into account in determining the coverage and appropriate risk levels in the NCC.
  • The cost of new buildings and housing in particular, is a crucial factor in driving affordability. Increasing the NCC stringency to improve building resilience in the face of extreme weather events comes at a cost. The primary goal is to ensure the benefits of any potential change exceed the costs. Where increased cost is unavoidable because of necessary health, safety, amenity or sustainability improvements, the increased costs must still be justified in accordance with the COAG best practice regulation guidelines.
  • The 2012 Productivity Commission Report Barriers to Effective Climate Change Adaptation states that in some cases, the vulnerability of people and buildings to climate change impacts will depend on how well building standards (which generally control how to build) and planning regulations (which generally control where to build) are integrated.
  • The challenges resulting from the potential for increased extreme weather events will in all likelihood change the way that many new buildings and plumbing systems are designed and constructed to withstand the requirements associated with different locations and to meet changing societal demands.

The discussion paper includes a number of questions, and the ABCB has prepared a response form which can be downloaded here and lodged via email. Responses are due by 1 July 2014.