Sustainable architecture: Understanding LEED and BREEAM certification

In the sustainable architecture field, there are two certifications that stand out for their importance and global recognition: LEED (Leadership in Energy and Environmental Design) and BREEAM (Building Research Establishment Environmental Assessment Method).

Both certifications seek to promote the construction of more sustainable and efficient buildings, but each has its own approach and methodology. This article presents an overview of these two certifications, their differences and similarities, and how architects can benefit from their application.

LEED: An holistic approach

LEED is an internationally recognised certification that focuses on energy efficiency, indoor air quality, material selection and design innovation.

LEED buildings are evaluated in several categories, including site sustainability, water, energy and air efficiency, materials and resources, indoor environmental quality, design innovation and regional priority. LEED certification is awarded at four levels: Certified, Silver, Gold and Platinum, depending on the number of points a project accumulates.

BREEAM: Pioneer in environmental assessment

BREEAM is the oldest and most widely used environmental assessment methodology for buildings. Like LEED, BREEAM assesses buildings in several categories, including management, health and well-being, energy, transport, water, materials, waste, land use and ecology, and pollution.

However, BREEAM also includes additional categories such as climate change adaptation and durability, reflecting its emphasis on long-term sustainability.

LEED and BREEAM compared

Although LEED and BREEAM share similar objectives, there are significant differences, as we’ll see below:

Approach to certification:

LEED tends to focus more on energy efficiency and design innovation, while BREEAM places greater emphasis on project management and climate change adaptation;

Scoring system:

BREEAM uses a weighted scoring system that can give more weight to certain categories, while LEED awards points more evenly;

Evaluation categories:

Both certifications assess buildings in a series of categories, but BREEAM includes additional categories such as climate change adaptation and lifelong resilience, reflecting its emphasis on long-term sustainability;

Global recognition and use:

Although both certifications are recognised internationally, LEED is more popular in the United States, while BREEAM is more common in Europe;

Certification process:

The BREEAM certification process is considered more rigorous and detailed, while LEED is known for its flexibility and adaptability to different types of projects;


In general, BREEAM certification can be more expensive than LEED certification, although this can vary depending on the size and complexity of the project.

Examples of LEED and BREEAM certified buildings in Spain and Portugal

In Spain, the Merlin Properties – Ribera del Loira 60 building in Madrid is an example of a LEED-certified building. This building has been recognised for its energy efficiency and sustainable design.

Another example is the Allonbay Village urban regeneration project in Alicante. This urban intervention was the first of its kind in Spain to achieve BREEAM Urbanism certification.

There are many LEED and BREEAM-certified buildings in Portugal. These buildings, like their counterparts in Spain, have been recognised for their commitment to energy efficiency and sustainability.

One such example is the Sonae Maia Business Centre, located in Maia, which obtained the first LEED certification with the “Gold” performance level in Portugal in 2008.

Porto Office Park (POP) was awarded BREEAM certification, making it the first building in Portugal to be rated “Excellent” in this certification.


For architects, understanding LEED and BREEAM certification is essential for designing and constructing sustainable buildings. Although each certification has its own approach, both offer a valuable framework for assessing and improving the sustainability of buildings.

By selecting the certification that best suits their needs, architects can help promote sustainable construction and contribute to a greener future.

More posts

Alubuild® achieves DIT Plus certification
Architecture and Cinema: a visual dialogue
Beyond Riken Yamamoto: 5 Japanese Pritzker Prize-winning architects
Ventilated façade and ETICS: Main differences and similarities between systems