Cooper Green Design | The Blog

I love the question asked of Paul King by a Drexel University student at Greenbuild today. She simply asked him to give his personal definition of “sustainable.”

Five years ago at Greenbuild, it seemed that everyone was caught up in semantics: Green vs. Sustainable vs. Eco-friendly vs. Bio-inspired. Various definitions were overly debated and argued, with no real outcomes. Since then,the arguments have largely been forgotten. What has emerged is some significant criticism of the LEED rating system, much of it centered on shortcomings such as a lack of robust metrics, exclusion of life-cycle cost measurements, and failure to adequately address zero-carbon goals.

While these criticisms are valid, the early goals of the LEED Rating System stated that certification should be “achievable” with a reasonable approach and level of effort and experience. I’m going to briefly revisit some of the old definitions.

Sustainable Building: A building that is

• CONSTRUCTED with environmentally benign and local materials
• OPERATED without adverse environmental or human health impacts
• Relies completely on RENEWABLE ENERGY and emits 0 green house gas emissions
• DECONSTRUCTS into 100% reusable or recyclable components at the end of its useful life

(my definition, adapted from an early USGBC definition)

Green Building: A building that

Uses design, construction, and operations practices that significantly reduce the negative impact of buildings on the environment and occupants through

• Sustainable site planning
• Safeguarding water and water efficiency
• Energy efficiency
• Conservation of materials and resources
• Indoor environmental quality

(from a 2002 USGBC training workshop)

Using the above definitions, “Green” is the weaker of the two, but the one that is behind the LEED Rating System. “Sustainable” is possible, but somewhat vague and more difficult to achieve. I’m of the opinion that over time, the definition of a “Green” building should have evolved to become synonymous with “Sustainable” building, and the LEED Rating System along with it. It is not there yet.

I generally tell my students and clients that LEED certified buildings are green buildings, which is not the same thing as sustainable buildings.

Back to Paul King and the Drexel University student’s question. He answered her by referencing the Brundtland Commission’s definition “one that meets the needs of the present without compromising the ability of future generations to meet thier own needs.”