NABERS embodied carbon tool taking shape

The work by NABERS towards launching an embodied carbon tool in mid-2024 has taken another stride forward following the release of a paper detailing the results of its public consultation, and responses to key questions about the tool.

As the grid decarbonises and buildings move away from fossil fuels to all-electric systems, there is a growing awareness of the need to address embodied emissions, generated by the production, transport, refurbishment and end-of-life processing of building materials.

Australia has no consistent method of measurement for embodied carbon, so developing a consistent method for measuring, benchmarking and verifying embodied carbon is a critical step towards enabling Australia to achieve its net zero emissions target by 2050. After a feasibility investigation in 2021 indicated strong support for a NABERS tool for measuring embodied carbon, the organisation took on the task.

In December 2022, NABERS released a consultation paper to help shape the embodied carbon tool. As in the earlier stages of consultation, industry was heavily engaged and supportive of the need for a tool and the overall approach.

NABERS received almost 80 responses from a broad variety of stakeholders, including building product manufacturers, building owners and developers, engineering and sustainability consultants, quantity surveyors, architects, life-cycle assessment experts, government policy-makers and academics. Several of these responses were from industry bodies, representing broad sectors of the built environment.

The consultation response paper runs through aspects of the proposed tool and the issues raised during the consultation. One key question for those in the HVAC&R space was whether the new system would cover “cold shell” or “warm shell” buildings – and which elements of building services would be in scope.

NABERS notes that the difference between the concepts of cold shell and warm shell were difficult to communicate in the consultation process, and don’t apply equally to all building types. Rather than sticking with these definitions, NABERS plans to clearly communicate which building elements are in and out of scope for each building type.

Building services related to the core of the building will be in scope for all building types. This includes major mechanical services such as HVAC, primary equipment associated with fire systems, vertical transport systems, and ducting and equipment associated with a building’s core. Some aspects of the building such as minor ducting and cabling out to the floor level won’t be included, because NABERS notes they are difficult to measure and represent a relatively small proportion of emissions.

Another concern raised during the consultation was the lack of emissions data for mechanical services equipment such as HVAC systems and onsite power generation. NABERS is conducting “emission factors” consultation with industry to determine appropriate data sources. Mechanical equipment in particular has a lack of data availability through EPDs, so NABERS will investigate whether it is possible to use TM65 measurement results.

In line with the principles discussed in the consultation response paper, NABERS has started developing the embodied carbon tool. This includes developing comparison benchmarks, certification rules, and training for NABERS Assessors, among other major deliverables. NABERS aims to launch the embodied carbon tool in mid-2024.

More information on the development of the embodied carbon tool and the results of the consultation are available at the NABERS website.

Photo by Pixabay.