Tilt-Up, Sustainability, and the Environment
By Ashley Kizzire, Constructive Communication, Inc. akizzire@constructivecommunication.com
Q&A WITH JIM BATY
For a few years now, green building and sustainability have been two buzzwords often touted in the design and construction industry. As more owners and designers explore this trend, it is important to understand the benefits that the Tilt-Up system provides. Jim Baty, TCA Technical Director, recently sat down to answer a few questions about how Tilt-Up is effective for meeting green and sustainable goals.
Q: How has the push toward sustainable projects affected the Tilt-Up industry?
A. The issue of sustainability seems to be tangential to the progress of the Tilt-Up industry. Some key projects have demonstrated success in coupling a myriad of sustainable solutions with a Tilt-Up structural shell. What is perhaps more interesting is that the decision to design and construct a sustainable project still does not involve as much consideration for the building envelope as perhaps it will or should.
Q: Why is Tilt-Up a good solution for green and sustainable projects?
A: Before sustainable design became a motivation, quality projects were constructed based on the concepts of creating building envelopes that minimized the dynamic changes in temperature of the climate surrounding the building. Passive solar design and thermal mass are two key phrases that came from significant works during the late 1970s to the early 1990s. These two concepts speak to the ability of the primary building structure to control the interior building climate, while allowing solar energy to enter in significant quantities and store that energy for later use. The characteristics of thermal mass are very prominent in Tilt-Up construction. According to passive solar design principles, the maximum amount of thermal mass that can be actively or effectively used in a 24-hour temperature cycle is 6 inches. There are very few Tilt-Up projects constructed with panels less than 6 inches in thickness. The location of the mass, another critical factor in the success of that design methodology, is ideal with the mass adjacent to or surrounding the built environment. Therefore, as sustainable projects seek performance from the building envelope to play an increasing role, Tilt-Up is positioned to provide the optimum combination of thermal mass, location and effective insulation. These are the thermal benefits to the sustainable design process.
There are additional reasons why Tilt-Up is a good solution for sustainable projects. For instance, all of the components for the structure can be provided through local sources, which is a major benefit to the Tilt-Up method. Many in the sustainable movement consider cement high in embodied energy, yet this is only a fraction of the product components for a Tilt-Up structure and one that continues to be refined both in process and percentage. The local production of the actual construction material (i.e., ready mix) in such high quantities offers far more benefits to the rating than the impact of the raw material production. However, let’s not overlook the life cycle of the Tilt-Up building. Where most projects often compared with Tilt-Up will either wear out or degrade beyond maintenance in a period of 15 to 30 years, the Tilt-Up building can withstand 50 or more years of use. This is certainly a testament to the quality of the materials and the timelessness of the construction. The Tilt-Up building not only proves to stand the test of time but does so with a very low maintenance profile, keeping costs and product consumptions low.
In addition, new technologies are increasing Tilt-Up’s ability to provide a sustainable structure. A few of these examples include new modular wind turbines, concrete-friendly thermal windows and a broadening range of insulation systems. These are clearly products that enhance the Tilt-Up structure or capitalize on the quality of structure created rather than modifying the existing technology demonstrating an interest in industry partnerships beyond the primary structure.
Q: How have Tilt-Up professionals responded to the need for sustainable projects?
A: In our estimation, Tilt-Up professionals have responded to the interest in sustainability by gaining an even greater understanding of their construction method — both the positive aspects of Tilt-Up construction regarding sustainability as well as the shortcomings. No one product or method alone perfectly achieves sustainability or high ratings on a green scale. All building systems need to be considered, including lighting, water, power, site, heat islands, etc. Therefore, the Tilt-Up professional has demonstrated ways to incorporate Tilt-Up as part of the solution or the goal of creating a project that can be labeled as sustainable. This has been accomplished by identifying the criterion for consideration of concrete’s role in the established rating systems as well.
Q: What are some of the environmental impacts of Tilt-Up?
A: There is still a lot to be determined when it comes to the environmental impacts of Tilt-Up. This is mainly because the focus on “impact” is such a relatively new topic and the concept is not fully understood. We know Tilt-Up has a very positive effect on reducing energy costs. Tilt-Up buildings have a tighter structure and less air infiltration compared to many of the competing systems. This is combined with optimum insulation, culminating in maximized thermal mass performance; Tilt-Up is very difficult to top when it comes to overall energy performance and structural and cost-efficiency. We also know there are many benefits to the environmental impact of lowering maintenance costs and reducing facility needs through longer life cycles. These are often viewed as intangible benefits in our “throw- away” society, but the practical and investment-minded owner realizes quickly the benefits of looking beyond the typical 15-year building life.
Q: What is the TCA doing to help members understand green building?
A: Whether you call it sustainability, green building or environmental impact, one of TCA’s goals is to educate the industry — both owners and solution providers — on the opportunities and the requirements of green building. We began visiting this topic three years ago at our final bi-annual Tilt-Up Symposium that later transitioned into an annual convention in Atlanta (2005) as well as at our architectural-focused Design Charettes. Key seminars continued this commitment during the 2006 convention in Denver with project profiles on successful LEED-rated projects and housing markets that are pursuing Tilt-Up. In addition, a major component of the Tilt-Up message during regional promotion events is the issue of sustainable solutions. Our goal is to educate our members and the market not only on what environmental impact Tilt-Up can have but what the goal for impact really is.
Q: How should Tilt-Up professionals market and sell Tilt-Up as a green solution?
A: I caution the focus on any one product or method as a comprehensive green solution. The concept of sustainability is so large that no one solution and no one component of building solutions is enough to make this approach effective. As was demonstrated during the Annual Convention in Denver last year, the decision to produce a sustainable solution in today’s commercial market remains a costly and intensive decision. However, the benefits of this decision on the built environment are far more significant. Can Tilt-Up be a part of a green solution? Absolutely! It has many positive benefits for such a solution — a great many more benefits than detractors. Should it be marketed solely on its greenness? I don’t think Tilt-Up professionals would do service to their customers by suggesting Tilt-Up qualifies a project to be labeled as green.
Q: Are there any misconceptions about Tilt-Up and how it is a sustainable solution?
A: I certainly think there are misconceptions on both positive and negative sides of the coin. The industry’s focus on concrete being high in embodied energy and therefore not a viable source for green solutions is a very big misconception. All construction materials suffer either in embodied energy, transportation energy or resource depletion. This is a fact of building in the past and one that remains a fact today. The raw material, Portland cement, at the heart of this argument does require energy to produce. Today’s professionals, however, supplement with other cementitious products such as slag and fly ash to reduce the overall percentage consumption. However, slag and fly ash also have some embodied energy. Regardless, the availability of ready mixed concrete as a local resource is as positive as the embodied energy is negative. Equally, a misconception is the idea that simply efficiently enclosing a space with an energy- efficient building envelope is enough to qualify a project as sustainable or green. In fact, there are so many other variables involved in a truly sustainable solution that excessive focus on the building envelope sometimes can reduce the ability to become highly rated as sustainable. A holistic system approach must be taken, and this is one of the primary reasons why the Tilt-Up industry continues to promote thinking of Tilt-Up solutions as “system solutions” and not components.
Q: Are there any codes or regulations that affect how Tilt-Up can meet environmental trends?
A: At the present time we are not aware of any such codes or regulations. There has been a lot of progress in energy code development to require higher-performing building envelopes. This has coincided with significant research to provide a more realistic understanding of the way buildings perform in the built environment. We have a long way to go to completely change our process of building toward methods, products and designs that emulate our more energy-conscious colleagues in Europe and other parts of the world.
