Ten categories of sustainability are assessed and within each of these categories a number of issues are examined. For example, under the Energy category, credits are awarded for construction that allows low CO2 emissions, employs low or zero carbon technologies, energy sub metering and energy efficient building systems such as insulated panels. See table 1 for a breakdown of the categories and associated issues.
A performance target is set and assessed for each issue, and if achieved the number of available BREEAM credits can be awarded. The targets are set to go beyond legislative requirements and challenge the design team to strive for levels of excellence.
Although a number of the issues have minimum standards which must be achieved in order to attain a particular BREEAM rating, there is also a degree of flexibility as the majority of the issues are tradable, allowing the specifier or client to choose which areas to focus more attention on. It is worth noting that in order to achieve an Excellent rating a minimum standard of 6 credits must be achieved in the Energy category, Ene 1 – reduction of carbon dioxide emissions category, and a minimum of 10 credits is needed to achieve an Outstanding rating – by far the highest number of credits for any of the issues. Other issues only ask for 1 or 2 credits, even at the Outstanding level. This clearly indicates how important the issue of reducing CO2 is considered to be. See table 2 for the overall minimum standards.
BREEAM also has an impact on regulatory requirements. For example, since May 2008 all new non-domestic buildings funded by the Welsh Assembly Government and Assembly Government Sponsored Bodies (AGSB’s) must be built to the Building Research Establishment Environmental Assessment Method (BREEAM) “Excellent” standard, or equivalent.