There are numerous benefits of using rating tools. The overall goal is to have a common set of criteria and targets, and these are typically embodied in design guides that help professionals to design, construct and manage property more sustainably. One benefit is raising awareness of environmental issues and standards and the assessment tools recognise and encourage best practice and stimulate the market for sustainable construction and property. This is apparent is the marketing and rental levels
achieved by sustainable buildings (PCA 2008). A further benefit of the tools is that they provide a verifiable method and framework for professionals to use. In many cases the tools set criteria and standards which go beyond the building codes and regulations in the countries in which they are used. However it is also possible to link the tools to government policies and regulations such as certification and labels and incentive initiatives. The EU Energy Performance Directive is a good example of this in practice. Finally, on an individual building level the adoption of assessment tools improves property management and prioritization of maintenance and operational needs to enhance sustainability.
Despite the many positive aspects, there are perceived shortcoming. One of the developers of the US LEED tool wrote in 2006 that LEED was ‘broken’ and needed to be fixed (Schendler 2006) arguing there was a disconnect between the concept and the reality of the tool in use. The assessment was prohibitively expensive, designers and owners were driven by scoring points and not by sustainability; a phenomenon term ‘LEED brain’. The energy modeling in the tool was ‘fiendishly complicated’ and the process was crippled by bureaucracy. Of greater concern was the ‘overblown claims for green buildings’ - thus was it possible that buildings having high LEED ratings were not actually that sustainable?(Schendler 2006). To-date the overall building assessment tools have been voluntary and not mandatory. Even the 2003 EU Energy Performance Directive is compulsory but requires disclosure of the energy performance rather than attainment of stringent performance targets. In Australia the Mandatory Disclosure Certificate of energy performance at the point of sale was enacted in 2010 and some impact may be expected in the future. The intention of the tools is to benchmark key sustainability standards and over time to increase standards, so whilst some are weak in areas changes will occur. Evidence suggests built environment professionals have embraced the SD agenda across many developed countries and are looking to the increased use of assessment tools. As yet however, we know very little about the equivalence and comparative uptake of the tools used internationally.
The development of rating tools
The current era of rating tools commenced in 1990 with the introduction of the BREEAM rating tool, and five years later this was followed by the French system, HQE, and by LEED in 2000 (figure 6). Further analysis of this diagram confirms that the evolution of rating systems into different countries is largely based on the initial rating systems; for example see BREEAM (Netherlands), LEED (Emirates) and Green Star (South Africa).
Figure 6. Timeline of the Development of Rating Tools