ZEMCH 2015 - International Conference Proceedings | Page 767

ia (Wilkinson, 2013). This legislation affects all new build and many adaptations; conversions are
required to comply with latest minimum standards. However the Australian minimum standards
are low and do not cover the operational phase, thereby buildings may comply with legislation
but still use excessive energy and water resources.
NSW (New South Wales) Residential stock is required to comply with the Building Sustainability Index (BASIX), which is administered through the National Australian Building Energy Rating
Scheme (NABERS). BASIX aims to deliver water and greenhouse gas reductions across NSW, and
is one of the strongest sustainable planning measures to be undertaken in Australia (BASIX, 2015).
Integrated into the planning system, BASIX is implemented under the Environmental Planning
and Assessment Act 2000 (EP&A Regulation) and State Environmental Planning Policy (Building
Sustainability Index: BASIX) 2004 (the BASIX SEPP). BASIX applies to all residential dwelling types
and is part of the development application process in NSW. Targets are calculated based on NSW
average benchmarks. The targets are; up to a 40% reduction in potable water consumption and;
up to a 40% reduction in greenhouse gas emissions. BASIX establishes minimum performance
levels for thermal comfort of dwellings. The BASIX benchmarks for water are based on the average
NSW annual potable water consumption from the residential sector, measured on a per capita basis; and for energy: on the average NSW annual GHG emissions from the residential sector on a per
capita basis. The benchmarks are determined from NSW average residential water, electricity and
gas consumption data collected from state-wide energy utilities by government departments.
For example, the NSW water benchmark is expressed in terms of potable water consumption and
is 90,340 litres of water per person per annum. Whilst the NSW energy benchmark is 3,292 kg of CO2
per person per year. Australian per capita emissions are amongst the highest in the world (ref). No
legislation exists in NSW in respect of landfill waste minimisation or other sustainability attributes.
Economic factors are very important, where economic lifespan covers the period in which the
property generates more income than cost, or when the present value of all future income is
higher than the present value of all future costs. A property has to have economic viability to be
considered sustainable. The income a property can generate depends on the price, quality and
competition in the market; whilst costs are related to maintenance needs (Remøy, in Wilkinson
et al, 2014). Thus the economy has a very profound effect on the economic lifespan of property,
shortening or lengthening it considerably. Obsolescence that can occur when a building’s operational costs, technical or functional characteristics exceed the benefits of occupation is termed
economic, technical, or functional obsolescence. At this stage, the building is adapted or demolished (Blakstad 2001). Technical lifespan is the length of time during which the property can meet
the technical and physical demands needed to use the building and protect the health and safety
of users. Functional lifespan is the period of time during which a property complies with the user’s
functional demands. The three types of lifespan are interrelated. For example, if the functional
lifespan ends, this usually implies that the economic lifespan also ends. If the functional lifespan
ends, it is not possible to find a tenant for the building that means the building can no longer
generate income to cover the costs. The ending of the technical lifespan may cause the ending
of the functional lifespan; however it is often the case that a building is still in a technically good
condition when the end of the functional lifespan is reached.
Social sustainability attributes within a property can include the provision of amenities to enhance the wellbeing and health of occupants. For example, physical building embodiments of
social sustainability could be provision of a childcare facility in an office building or, a green roof
where staff can relax during breaks from work. Social attributes are often found in the Corporate
Social Responsibility (CSR) policies and reports of building tenants and may include charitable
donations given, in cash or kind, to less advantaged groups. Also social aspects may be embodied
in an organisations workplace terms and conditions.

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