Elements of concrete construction including cement stabilization, pervious concrete pavement, albedo pavement, insulated sandwich panels, reduction of construction waste, fly-ash pozzolans, reinforcing steel and use of local aggregate all help achieve LEED credits in categories such as construction waste management, recycled content and local/regional materials. When these factors are all added together, the 21 points are achievable.
Sustainability key to green
One of the key components of green design is the concept of sustainability. According to the World Commission on the Environment and Development (WCED), sustainability is"a form of development that meets the needs of the present without compromising the ability of future generations to meet their needs." Too often, construction professionals get trapped in the present with looming deadlines and demanding projects. With such challenging schedules and tight budgets, this is easy to do. However, green builders and designers must account for the impact their buildings have on future generations.
A systems approach should be used to determine a product's energy requirements – energy consumption at each state of a product's life cycle, beginning at the point of raw materials extraction from the earth and proceeding through processing, manufacturing and fabrication, end use and disposal.
In some instances, end use can account for as much as 90 percent of a product's impact on the environment. Transportation of materials and products to each process step also must be included in the assessment. These principles hold true for any construction project. To be a green builder or designer, sustainability must be at the forefront of your mind and early design consideration.
Does energy efficiency = green?
A common misconception that arises in many discussions of green building is that energy efficient is synonymous with green. We are all aware that tilt-up is an energy efficient solution, so the trend in debates about tilt-up's green attributes is to provide the standard laundry list of this construction method's energy efficient characteristics. However, energy efficiency is only one component of green design.
To truly be a green solution, all elements of the LEED project checklist must be considered to include sustainable sites, materials and resources, as well as innovation and the design process. Energy efficiency accounts for only 17 of the possible 69 points for a LEED registered project.
Beyond energy efficiency, tilt-up uses locally produced materials. This provides a tremendous savings in terms of transportation costs. And, since the panels are cast on-site, an even greater savings is realized. Further, tilt-up is extremely versatile and reuseable. So, the next time you are asked about tilt-up's green attributes, be sure to include these components, as well as energy efficiency in the discussion.
How to make it happen
The durable, thermal mass and recyclable attributes of concrete make it a key player in the search for green and sustainable solutions, which makes education about this topic critical. Concrete helps the quest for sustainable and green design through the use of recycled steel and fly ash. And, site cast tilt-up concrete construction is building upon these attributes.
The 2004 TCA Achievement Award winner in the Technical Innovation category is an example of how green is becoming more than just a buzzword, but rather a design principle. This project included the construction of a massive tilt-up wall in the center of the EPA Region VII Science and Technology Center in Kansas City, Kan. To meet the green building prerequisites, 20 percent fly ash was integrated into the mix design in lieu of cement. The project achieved the LEED Silver Certification rating.
One sure way to differentiate your firm from the competition is your knowledge of the latest trends in your industry. It is clear green is a trend that is here to stay, so taking the time to learn the basics now will set your firm up for success.
Charles M. Popovich, Jr., AIA, LEED-AP, CSI, is a project manager/architect in LJB Inc.'s architectural department.
Michael F. Sugrue, P.E., LEED-AP, is a principal in LJB Inc.'s Commercial and Institutional business. He is also a past president of the Tilt-Up Concrete Association and a member of a joint concrete industry task force that liasons with the Army Corps of Engineers.