Sustainability Assessment tools – comparison

The type of building to be assessed determines the potential tools available for assessing that building. It is not always practical or possible to achieve an assessable 5 or 6 star rating for some buildings. The most common rating tools can be reviewed briefly as follows:

1. Residential energy ratings – NatHERS (Nationwide House Energy Rating Scheme) rating – this is the commonly known 6 star (previously 5 star) rating that is the benchmark mandatory level required to be achieved for residential houses. The rating assessment can be undertaken using any of the FirstRate5, Accurate or BERS rating tools. A HERS rating is only available to residential houses and multi unit developments (class 1 & 2 buildings). A HERS rating or a Part 3.12 Building Code deemed to satisfy assessment is mandatory for all new class 1 & class 2 buildings and extensions. HERS ratings are undertaken on the design of these buildings. Commercial buildings of class 3-10 cannot be rated using any of the three tools, and cannot obtain a HERS rating. BCA Section J assessments are required for such buildings.

2. Green Star rating – Green star ratings are available for a range of buildings but at this stage not all buildings. Green Star rating tools exist for the following building types: Office structure and interior, Office interior only, Education, Healthcare, Industrial, Retail, and Multi-unit residential buildings. Pilot tools are being developed for Convention Centres, Public buildings and Custom buildings. Green Star ratings range from a 4 star building to a 6 star building. There is no higher rating availbable. A 4 star Green Star building represents a building in the top 25% of buildings nationally in terms of its sustainable design. A 5 star Green Star building represents a national best practice building. A 6 star Green Star building represents a worlds best practice green building. Obtaining a Green Star rating is a voluntary accreditation. The process of achieving a Green Star rating is usually integral with the design of a building, and requires a lot of design consideration, time and document substantiation. It is not an in-expensive process and would practically mainly only be considered for projects above $3M in value or where the client has a very strong commitment to achieving a very high standard of sustainable design in their building.

3. NABERS (National Australian Built Environment Rating System) rating – NABERS unlike the above two rating tools is a performance based rating system for completed / existing buildings that relies on 12 months of operational data before a rating can be determined. NABERS assessments can be completed on the following building types: offices, homes, hotels, retail, schools, hospitals, and transport. NABERS ratings range from 1 – Poor performer 2 – Below average performer 3 – Above average performer 4 – Strong performer 5 – Top performer 6 – Best practice.

4. Building Energy Efficiency Certificate (BEEC) – commercial building mandatory disclosure – as of 1 November 2010 under the national Commercial Building Disclosure program the owners of all commercial buildings over 2000m2 will be required to undertake and disclose the results of a BEEC to prospective tenants or building buyers. The BEEC involves 3 components: a NABERS base building energy efficiency rating, a tenancy lighting assessment, and behavioural energy efficiency guidance. NABERS energy ratings which assess the infrastructure of the building, must not take into account Green Power. A BEEC is valid for 12 months. For further information on the mandatory Commercial Building Disclosure program refer to www.cbd.gov.au

5. BCA Section J compliance – compliance with Section J of the Building Code of Australia is mandatory for all commercial buildings. These assessments must be completed for a commercial building to obtain a building permit. There is no star rating applied with these assessments, however a report is required to be completed to confirm compliance in energy efficiency areas.

6. Sustainable Design Assessments for the Planning Process – These assessments can utilise the STEPS or SDS tools (for residential or commercial buildings respectively) or for larger residential or commercial developments more extensive Sustainable Design Assessments may be required. The more extensive reports are variously termed ESD reports, ESD Management Plans, Sustainability Management Plans, or Sustainable Design Statements by differing councils. About one third of Victorian Councils are now implementing Sustainable Design Assessments as a requirement in their planning permit process.