Seeing Green

Concrete Industry Seeks Ways to Foster Sustainable Development

by Natalie Keith

Like others in construction, the concrete industry is seeking ways to introduce green building principles.

"We don't have to agree with the tree huggers on all points, but I think we all care about the subject," said Martin Detling, a professor at Columbia University and one of the speakers at a Concrete Industry Board luncheon on the subject in January.

Other speakers were Robert Fox, partner, Cook + Fox Architects; and Richard DeMarco, associate partner, SLCE Architects.

While the use of concrete has many advantages, such as its durability, affordability and availability, it also has an impact on the environment because of the natural resources needed to produce it.

There are 500 million tons of concrete produced in the United States and 10 billion tons produced worldwide each year. The industry uses 1 trillion liters of water each year during the production process.

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The concrete industry accounts for 7 percent of the total carbon dioxide emissions, and a high level of carbon dioxide emitted into the atmosphere has been linked to the greenhouse effect and global warming, Detling said.

Fox added, "When you're responsible for 7 percent of the carbon dioxide production in the world, that's a big deal."

Another reason the industry must address environmental issues related to concrete production relates to its ability to compete with steel, which requires less energy to produce. However, DeMarco pointed out that concrete must be prepared near a worksite and requires less energy consumption with regard to transportation.

Among ways the industry can enhance sustainability qualities of concrete are to increase the use of recycled materials such as fly ash and blast furnace slag in concrete production; improve the durability of the produce so it lasts longer; and find new ways to deliver concrete to worksites, such as train or ferry, which require less fuel consumption.

"We don't own this earth, we are borrowing it," DeMarco said. "We need to leave it to our children in the best shape we can."

William Lyons III, director of engineering sales at Separation Technologies Inc. who attended the luncheon, cautioned that the amount of fly ash used in concrete must be optimized, especially during the winter months. If concrete contains too much, it will increase the time required for it to harden, and that delays construction.

"You can speed up the hardening process by adding an accelerant, but that adds to the cost of the product," he added.

On the road to instituting more green practices, however, the concrete sector will likely face many of the same obstacles encountered by others in the construction industry, including increased costs.

In his address, Detling shared details about the Solaire, the green residential building recently completed by the Albanese Organization on behalf of the Battery Park City Authority.

The Solaire contains concrete, and under the green design principles adopted by the authority, products used for the project were evaluated based on how much recycled material they contained, how they were manufactured, how they transported to the site and other factors. Products were selected only after meeting strict sustainability criteria.

Detling said the incorporation of green elements increased the construction costs of the base building by 15 percent.

"But you end up with a building that's more marketable," he added.

Currently, there are no laws that require the industry to adopt green principles, but the U.S. Green Building Council developed a program whereby projects are rated according to the adherence to sustainability practices. The LEED (Leadership in Energy and Environmental Design) Green Building Rating System is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings.

LEED standards are available for new construction and major renovation projects, existing building operations, commercial interiors projects and core-and-shell projects.

"A LEED building is known as a healthier building that lasts longer," Detling said. "Certain costs are higher."

LEED was created to define "green building" by establishing a common standard of measurement. There are no financial incentives to follow LEED, according to the council.

Under the LEED rating system, buildings can earn four levels of certification - LEED certification, silver level, gold level and platinum level. Currently, there are 852 projects across the country registered with the LEED program. Only two buildings in the United States have earned platinum certification status, according to the council.

Many cities and states are considering adopting LEED standards, Fox said. "Whether you understand it or think it's right, it's going to be here and be something you have to deal with," he added.