Terms like “sustainable design” and “green building” are not new at World of Concrete. For years, exhibitors have been touting their green products, and attendees have been asking about carbon dioxide emissions and recycled content. In fact, it's hard to go anywhere in the construction community without having such conversations.

In 2008, WOC further encouraged discussion by establishing Greensite, a special area dedicated to sustainability. Manufacturers, suppliers, and associations displayed poster exhibits and discussed green techniques and products. Videos and live presentations educated attendees on a wide range of issues, including pervious concrete pavements and thermal mass.

The message was that concrete has a great deal to offer sustainable construction. “The green-building movement recognizes the need to revisit the way we build structures and the materials we use to build them,” said Kristin Cooper-Carter, director of the Concrete Industry Management program at California State University, Chico, and a Greensite speaker. “Concrete has many green attributes, and with industry participation in extensive carbon-reduction efforts, cement and concrete have an important role in this new worldview.”

“You can look at this issue from several different viewpoints,” said Greensite speaker Brian Miller, director, engineering and technology at the Precast/Prestressed Concrete Institute. “From a scientific view, you may consider the impact construction has on our environment through global climate change or resource depletion.

“From a business viewpoint, you may consider that the general public is becoming more educated about sustainability, and every industry is changing how they go to market. Or from a government view, you may consider regulations at all levels of government. Soon, sustainability may not be an option, but a requirement.”

Differing viewpoints

Discussions and comments ranged from enthusiastic and positive to cautious and unconvinced. But since awareness was a major goal of Greensite, such conversations even taking place was a step in the right direction.

“There is much more awareness today, which is great,” says Greensite attendee Gina Neusteter Koshak, owner and chief designer of Los Angeles-based design and construction firm, Romneya. “A large part of it is consumer-driven. All across the country, contractors are putting themselves in the green niche.”

Yet green is becoming less a niche and more the way of doing business. “Concrete is a very sustainable construction material,” Miller said. “It is a natural material that is inert with the environment and provides several sustainable attributes, including long-term service life and durability, the use of recycled materials, no VOCs or harmful emissions, and thermal mass.”

That's not to say that concrete does not face challenges. Producing portland cement emits a great deal of CO2. But as David Shepherd, director of sustainable development at the PCA pointed out, manufacturing improvements have already significantly reduced CO2 emissions per unit of cement produced. And using more supplementary cementitious materials such as fly ash further lowers the environmental impact of concrete production.

The construction industry faces the challenge of determining exactly what being sustainable means. Is it defined by using recycled and environmentally friendly materials? Is it reducing CO2 emissions? Or is it longer service life and greater energy efficiency?

Green is truly a balance of these things. It is important to discuss new technologies and techniques and continue to define the industry's role in the increasingly sustainable world of construction. As innovation continues, it is a safe bet that next year's Greensite will be bigger and better.

— Jim Schneider is senior editor of ECO-STRUCTURE. E-mail jschneider@hanley wood.com.