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THE ROLE OF TILT-UP IN GETTING GREEN|
By Jim Baty, Technical Director of the Tilt-Up Concrete Association
It is almost impossible to flip through an industry trade magazine or visit an association website without finding a mention of green construction. However, if you feel a bit “green” about understanding this new trend, you are not alone. An August 2002 survey conducted by Buildings magazine and the Corporate Realty, Design and Management Institute noted that while 99 percent of respondents feel the green concept is important, 63 percent indicated that the trend is “not at all” or only “somewhat” understood by members of their firm. As such, the Tilt- Up Concrete Association (TCA) has committed to educating concrete contractors not only about the latest trends and developments in the green concept, but also the fundamentals of this new industry buzzword.
“We would be remiss as an industry trade association if we did not explore the basic tenets of this design concept,” said Ed Sauter, executive director of TCA. “Regardless of whether or not green affects your business, as a member of the concrete industry today, it is certainly a topic we must get our hands around so we can better understand the role of concrete in the trend.”
LEED HELPS DEFINE GREEN CONCEPT
The United States Green Building Council defines a green building as one that is “designed, constructed, and operated to boost environmental, economic, health and productivity performance over that of conventional buildings.” In order to quantify this definition, the Council developed the Leadership in Energy and Environmental Design™ (LEED®) rating system as the standard for green building. The Council defines LEED as “a voluntary, consensus- based national standard to support and validate successful green building design, construction, and operations LEED offers third-party certification of qualifying buildings, high-performance design guidelines, and professional training and accreditation services.”
With LEED, a total of 69 points can be awarded in the following six areas:
· Sustainable Site (14 points – 20%)
· Water Efficiency (5 points – 7%)
· Energy and Atmosphere (17 points – 25%)
· Materials and Resources (13 points – 19%)
· Environmental Quality (15 points – 22%)
· Innovation and Design Process (5 points – 7%)
Three levels of credit for buildings are available based on the point total:
· LEED certified: 26 – 32 points
· Silver Level: 33 – 38 points
· Gold Level: 39 – 51 points
· Platinum Level: 52 – or more
The use of concrete in buildings dramatically helps achieve a strong LEED rating. According to the Portland Cement Association (PCA), by using concrete as many as 21 LEED points can be achieved. Concrete itself can be recycled and can contain many recycled materials. Further, concrete is manufactured locally, so transportation costs are reduced. Anne Ellis, PE and Ray Porfilio, AIA, of Earth Tech explained during their presentation at the TCA Design Charette in September 2003 that of all the building materials, concrete has the lowest embodied energy. In other words, concrete uses less total energy from extraction of raw materials, transportation and production.
Many of concrete’s inherent properties make it a solution for the green trend. The thermal mass properties of concrete, reduced air infiltration and higher energyefficiency insulation systems allow concrete to be a viable green building product. By reducing air infiltration, a stable building environment can be created with specific temperature set points. Concrete’s reflective surfaces save energy by reducing temperatures by five-degrees, cutting air conditioning usage by 18 percent, and requiring less power to light the area at night. These attributes will add points to a building’s overall LEED point total.
WHAT’S ALL THE BUZZ ABOUT BEES?
Beyond green design and sustainability, the term “BEES” is being thrown around in green discussions. True green building design examines all products not merely in terms of green attributes, but as a sum of attributes through a Life Cycle Assessment (LCA) and environmental impact. LCA is an objective process used in the evaluation of the environmental burdens associated with a product, process or activity through the identification and quantification of energy and materials used and wastes released to the environment. The assessment includes the entire life-cycle of the product, process or activity, encompassing the extraction and processing of raw materials, manufacturing, transportation and distribution, use/reuse/maintenance, recycling and final disposal.
Developed by the Building and Fire Research Laboratory of the National Institute of Standards and Technology (NIST), Building for Environmental and Economic Sustainability (BEES) is an automated approach for measuring the lifecycle environmental and economic performance of a building product. All stages in the life of a product are analyzed with this system, including raw material acquisition, manufacture, transportation, installation, use, recycling and waste management. Economic performance is measured using the ASTM standard life cycle cost method, including initial
investment, replacement, operation, maintenance and repair, and disposal; and environmental and economic performance are combined into an overall performance measurement. Other federal agencies are helping in the funding of BEES (e.g., U.S. EPA, HUD’s Partnership for Advancing Technology in Housing Program), and some manufacturers are adding their products to the ecoprofiles, which will be included in BEES 3.0 version, to be released soon. For more information, visit http://www.bfrl.nist.gov/oae/software/bees.html.
SUSTAINABILITY KEY TO GREEN DESIGN
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.” Sustainability is essential to being good stewards of the earth.
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 building has on future generations. The American Plastics Council’s www.greenbuildingsolutions.org website states that, “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 m nd and early design consideration.
DOES ENERGY EFFICIENCY EQUAL 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 reusable. So, the next time you are asked about Tilt-Up's green attributes, be sure to include these components, as well as energy efficient 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. According to Michael Sugrue, P.E., vice president of CON/STEEL Tilt-Up Systems, “Concrete helps the quest for sustainable and green design through the use of recycled re-steel and fly ash.”
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 that green is a trend that is hear to stay, so taking the time to learn the basics now will set your firm up for success.
ABOUT THE TILT-UP CONCRETE ASSOCIATION (TCA)
TCA was founded in 1986 to improve the quality and acceptance of Tilt-Up construction, a construction method in which concrete wall panels are cast onsite and tilted into place. Tilt-Up construction is one of the fastest growing industries in the United States, combining the advantages of reasonable cost with low maintenance, durability, speed of construction and minimal capital investment. For more information about the TCA, visit
www.tilt-up.org or call Ed Sauter at 319-895-6911 or e-mail
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