Green Building Rating Systems in Construction

There are a number of green building rating systems which are used in the construction industry to evaluate (commercial) buildings according to the efficiency with which they use natural resources, and their overall impact on human health and the environment. 

Two of the more long-standing programs are the Building Research Establishment Environmental Assessment Methodology ("BREEAM") and the Leadership in Energy and Environmental Design ("LEED").  These are globally accepted programs which indicate that a building was designed and constructed to a certain level of environmental responsibility.

Since 1990, BREEAM’s third-party certified standards have helped improve asset performance at every stage, from design through construction, to use and refurbishment.  Millions of buildings across the world are registered to work towards BREEAM’s holistic approach to achieve ESG, health, and net zero goals. It is owned by Building Research Establishment ("BRE") which has over 100 years of building science and research background.

LEED is a voluntary rating system to certify sustainable buildings and neighbourhoods. Launched by the US Green Building Council ("USGBC") in 1998, LEED has been gaining traction around the world – in fact 1 of every 3 LEED projects is outside the United States. According to USGBC in March 2020, there were more than 100 certified projects in Ireland, of which 60% had achieved the certification in the previous two years.

The biggest difference between the two is how the rating is awarded.  BREEAM uses licensed assessors who examine the evidence against the credit criteria.  If the BRE decides the building meets its requirements, BREEAM accreditation is issued.  LEED on the other hand does not use assessors to collect evidence for certification.  Instead, the building’s design team collects data and sends it to the USGBC.  Once the data is examined, LEED certification is awarded if the building meets the requirements. 

Some other differences include:

• LEED’s thresholds are based on percentages, while BREEAM uses quantitative standards; and
• LEED is considered to be simpler in its approach, while BREEAM is more academic and rigorous.

Another rating programme which is new to this jurisdiction is NABERS UK, an adaptation of the highly successful NABERS programme that operates in Australia. Launched in 1999, NABERS is widely considered to be a world leading environmental performance rating tool for commercial buildings.

There are two product offerings available under NABERS UK for office buildings: (1) Design for Performance to drive energy-efficient new buildings, and (2) NABERS Energy ratings to measure how energy-efficient existing buildings are.

1. Design for Performance is the process whereby a developer or owner commits to design, build and commission a new office development or major refurbishment to achieve a specific NABERS Energy rating.
2. NABERS Energy measures the efficiency of an office building and rates its performance.  The energy rating works by comparing the energy consumption of a building against a set of benchmarks that have been developed using actual data.  NABERS ratings are valid for twelve months.  This annual model helps ensure that your rating represents a building or workplace’s current operational performance.

For more information please contact Rhona Henry and Kimberley Masuda or your usual Matheson contact.