Building control in Australia: energy performance

Measuring performance

2 August 2016

Continuing his series from Australia, Mark Anderson looks at energy performance

In November, the Building Services Research and Information Association announced plans to develop a prototype UK scheme based on the National Australian Built Environment Rating System (NABERS).

There are 3 similar schemes in Australia:

The first two rate building sustainability, with the main difference that Green Star rates design at conceptual and as-built stages, while NABERS rates operational effectiveness. BREEAM rates design and usage, and it is also internationally applicable. Table 1 compares them with the UK's energy performance certificate (EPC).

	Green Star	NABERS	BREEAM	EPC
Environmental impact reviewed	Potential	Actual	Potential and actual	Potential
Rating metric	Design	Performance	Design and performance	Design
Timing	Design phase and/or as-built	When in use (Ref. 1)	Design phase and/or as-built and when in use	Design phase and/or as-built
Properties covered	Office, multi-unit residential, retail, healthcare, education, industrial, office interiors	Office, residential, hotel	Office, multi-unit residential, retail, healthcare, non-residential	Office, residential
Section	- Whole buildings - Office fit-outs - Integrated fit-out and base building	- Whole buildings (Ref. 2) - Tenancies - Base building	- Whole buildings - Office fit-outs - Integrated fit-out and base building - Existing buildings	- Whole buildings
Ratings based on	Indoor environment quality, energy, water, waste, management, transport, materials, land use and ecology, emissions, innovation	Indoor environment quality, energy, water, waste management, transport, materials	Indoor environment quality, energy, water, waste, transport, management, land use and ecology, emissions, innovation, materials	Indoor environment quality, energy, materials
Certifiable ratings	4, 5 or 6 stars	1, 1½, 2, 2½, 3, 3½, 4, 4½ or 5 stars	1, 2, 3, 4 or 5 stars	A, B, C, D, E, F or G
Governing legislation	None - accreditation is voluntary, not mandated	Must disclose NABERS energy rating when selling or leasing (Ref. 3)	None - accreditation is voluntary, not mandated	Must disclose energy rating when selling or leasing
Source	Green Building Council Australia	NABERS	BREEAM	gov.uk (EPCs) and gov.scot (EPCs)

Table 1: Comparison of key features of Green Star, NABERS, BREEAM and EPC

As the NABERS prototype will provide useable data on the building after it has been constructed, it allows a new occupant to benchmark it against other similar buildings and be confident that, when they move in, they will have a good idea of likely running costs. It also gives facility managers a chance to fine-tune systems to occupants' needs and obtain results on its performance close to the original design.

Unlike Green Star or BREEAM, the NABERS prototype is more agile, but it does not necessarily consider all of a property's sustainable features. As NABERS is based on actual data from working buildings and EPC is not, adoption of the former would enable buildings to be more demonstrably sustainable for just a bit more effort. However, as an EPC requires less effort to obtain at present, it is likely to remain the preferred option unless NABERS is mandated.

If so, it will have merit in the marketplace. But it is also likely to be seen as an enhanced EPC nudging EPCs out of the market.

Mark Anderson is Senior Building Certifier at KPMG SGA

Further information

Ref. 1: A 'commitment agreement' made prior to building use allows a building owner to publicise the NABERS star rating sought
Ref. 2: Building must be 75% occupied (tenanted) to gain a whole building rating
Ref. 3: Applies to office buildings of 2,000 sq. m or more from November 2010 (under Building Energy Efficiency Disclosure Act 2010)
Read the other features from Mark's Australian series: Building control in Australia: issues raised by apartment fires
Related competencies include Sustainability
This feature is taken from the RICS Building control journal (June/July 2016)