Jorge Chapa

The Australian property sector’s international reputation is under threat by proposed changes to the National Construction Code, the Green Building Council of Australia has warned.

The GBCA has lodged a submission with the Australian Building Codes Board, with the aim of improving the quality of building stock across the board and protecting the property sector’s international reputation.

GBCA executive director – Green Star Jorge Chapa told The Fifth Estate the organisation had offered to share information on energy and thermal performance verification methodologies with the ABCB to increase the alignment between the code and international best practice.

Mr Chapa said it was part of the GBCA’s mission to drive better outcomes across the built environment, “not only at the top of the market where Green Star plays, but at all levels of the market.”

The GBCA also wants to see conceptual changes within the Building Code of Australia that highlight the importance of best practice energy efficiency and its linkages with reducing greenhouse gas emissions, thermal comfort, health and productivity outcomes.

Mr Chapa said one of the major concerns about the proposed changes was that these linkages have been entirely taken out, as the proposed NCC 2016 instead just sets legislated minimums for energy performance.

Australia’s reputation under threat

Mr Chapa said this would negatively influence how Australia’s building expertise is perceived worldwide. There would be no ability to say with confidence that Australia delivers best practice buildings as part of its core approach, he said.

“In reality the NCC has additional functions that aren’t just [about] legislated minimums. It also demonstrates Australia’s capacity to model complex buildings and energy solutions, and to model the relationship between energy and carbon emissions,” he said.

For international investors or others looking at the standards the NCC 2016 would enforce, it would then lead them to “think less of Australia’s capacity to develop world-class buildings.”

There will also be impacts in terms of the usefulness of the NCC as a communications tool with clients and others in the property sector about the link between GHG emissions and energy efficiency.

“It will be harder to tell people this is important,” Mr Chapa said.

“The NCC is an essential part of how we coordinate communications around greenhouse gas emissions, climate change and reducing greenhouse gas emissions [from the built environment].”

Building envelope energy efficiency also influences thermal comfort, and the health and productivity of occupants. Mr Chapa said these reasons needed to be stated more clearly, as for example, the rationale behind the fire safety provisions is stated and understood.

“If energy efficiency is communicated similarly [to fire provisions], it will lead to better outcomes.”

The resurrection of JV2

Other concerns the GBCA has expressed to the ABCB include the reintroduction of JV2 for demonstrating compliance with energy performance requirements.

This methodology, which was scrapped some time ago and has now been brought back, Mr Chapa said, lacks transparency and gives no guidance as to why a building either complies or doesn’t. There is also no explanation in any of the documents produced by the ABCB for the consultation period as to why it’s been resurrected.

“In some cases JV2 will result in a building fabric that’s not up to the current standards – one that is less efficient, less comfortable, less healthy and less productive,” he said.

The problem of whole building energy assessments

Another concern is the shift of Class 2 buildings, multi-residential apartments, to a whole building assessment methodology as is applied to commercial buildings.

Where a methodology like JV2 allows for a poorer outcome than current standards, or where JV3 modelling also delivers a building where there are apartments with extremely poor performance, Mr Chapa said it will mean a need for more frequent – and generally expensive – retrofits.

“If the drive [of the changes] is to lower the costs of construction and compliance, this won’t help, it is just deferring the cost,” he said.

He also said the change to whole building modelling would make it “very confusing” for buyers of apartments.

“It will hurt people overall. The current system allows people to know that a unit has a specific NatHERS rating,” he said.

“The change will not do that.”

Where the building fabric is the problem in terms of energy performance, it’s the major aspect residents cannot change. They can’t open walls and add more insulation. They can’t change the glazing. They can’t fix a leaky facade.

In a standard high-rise, units on the side with poor solar orientation (if the building fabric is also a poor performer) are “stuck” with thermal issues. It’s something a buyer can’t control, and there will be no way for them to easily find out what the performance will be until they are living in it.

Mr Chapa said for these reasons, there was still a need for the BCA to address the performance of the building fabric at an individual unit level, so at least people could have some confidence they would not be purchasing a really bad apartment.

He said there were also other important benefits the BCA delivered ensuring energy efficiency on an individual apartment level. These include reducing noise ingress and ensuring the building envelope is capable of both proper ventilation when required and preventing ingress of condensation and subsequent mould growth.

Some solutions

One of the solutions the GBCA has suggested to the ABCB is that thermal imaging and an air pressure test be required to demonstrate compliance. Mr Chapa said this would be a simple method for verifiers to use to prove outcomes, and is in line with international best practice. In the UK for example, a pressure test for air tightness is required for any building.

At this point, he said the ABCB did not have a remit to check for compliance with the code – this is the responsibility of state and local governments. However, this could be changed and the level of stringency increased in NCC 2016.

Other aspects the GBCA wants to see addressed include the training of building certifiers, again, with an eye to international best practice benchmarks and stated values for energy efficiency.

“We made a comment in our submission that with all the changes around JV2 and JV3, if they have a well-trained body of certifiers they probably will work,” Mr Chapa said.

“People are hungry for increased stringency and people are hungry to engage with the ABCB around training and verification.”

The GBCA also wants the NCC to recognise Green Star’s methodologies for energy efficiency and thermal comfort compliance, which Mr Chapa said have demonstrated their success in delivering high performance outcomes over many years.

Mr Chapa said the success of the ratings showed what can be achieved through good building practices, and that there was an “appetite” for sustainable buildings.

If the NCC were to recognise these methods, it could be used as a mechanism to increase the sustainability aspirations of Australian building stock. Mr Chapa said it would also help users of the code to see the value of more stringency.

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