In the red corner, representing the US, we have LEED, while in the blue corner we have Britain’s finest, BREEAM. The two tools for measuring the sustainability of buildings are locked in a battle for global dominance.
Given the part the construction industry will play in cutting carbon emissions - buildings account for 44 per cent of the UK’s CO2 - a system to rate how green new and existing buildings are is essential.
Until now, BREEAM has dominated in Europe, with LEED making inroads in much of the rest of the world due to its adaptability - meaning it doesn’t need to be formally adopted as a country’s official sustainability tool.
More than 110,000 buildings are certified and over half a million are registered with BREEAM. The number of buildings certified by LEED is relatively modest at around 20,000. But every day, £304 million of construction projects register with LEED. Last month, Italy became the first European country to commit to LEED.
The main difference between the two methods is the process of certification. BREEAM has trained assessors who assess the evidence against its credit criteria and report it to the Building Research Establishment, who validate the assessment and issue the certificate.
While LEED does not require training, there is a credit available if an accredited professional is used. The role of the professional is to help gather evidence and advise the client. The evidence is then submitted to the US Green Building Council, which does the assessment and issues the certificate.
Both tools share common components. Early involvement of the assessor at the design stage is beneficial to the project and the final rating. Both tools drive the market to improve building design. The judging criteria also keeps pace with legislative developments and current best practice.
BREEAM is funded from the licence fees for the assessor organisations, on a scheme-by-scheme basis, and also the project licence fees. LEED is funded in part by the licence fees, which tend to be higher than BREEAM, but also through USGBC memberships.
Each rating tool typically references local building codes and varying modelling tools, each with different ways of measuring and illustrating energy, carbon, water and material impacts. This is for a good reason: each country, and often region, will vary in terms of legislation, climate, geography and resources.
To deal with this problem, the different sustainable rating tool providers have briefly downed arms to try to establish an agreed set of metrics that will allow a means of measuring, reporting and verifying improvements in a consistent and comparable way.
This is happening in a joint partnership between the United Nations Environment Programme Sustainable Building Climate Initiative, World Green Building Council and Sustainable Building Alliance, supported by the rating tool providers.