The word sustainability is getting a lot of use these days. A simple Google search of the word yields more than 25 million results. However, sustainability is not a mere “pie in the sky” concept for think tanks and talking heads; it is a concept that needs to be embraced by everyone in the building and construction profession.
As sustainable development practices become increasingly common, everyone in the construction industry will have to become familiar with these practices to stay competitive and be successful. This is equally true for the concrete contractor.
But what role should the concrete contractor play in the evolution of sustainable construction? Before answering this question, it's worthwhile to take a quick look at sustainability and what it means.
Rapid recognition
Sustainability has been slowly growing as an important issue in construction since the 1970s but has seen rapid recognition in the past few years, particularly with the emergence of the U.S. Green Building Council (USGBC) and its Leadership in Environmental and Energy Design (LEED) rating system.
Sustainability in the construction industry is not limited to new materials, but about changing behaviors and building practices. It's also not limited to ecological and environmental matters, but about the economic and social impact as well. The convergence of considering the environmental, economic, and social implications is referred to as the “triple bottom line.”
Recycling aluminum cans is one example of a sustainable practice contributing to the triple bottom line. Environmentally, it means there is less mining for virgin materials and a decrease in manufacturing and energy used. As an economic consideration, it is less expensive to produce new products from recycled aluminum. On the social front, recycling aluminum keeps dollars in the local economy instead of importing new materials, and the practice reduces landfill waste. These are a few reasons to recycle aluminum, but they illustrate the principles of the triple bottom line for a practice to be considered sustainable.
Without consideration for the economic and social implications, the environmental implications will fall on deaf ears. Just five years ago, it was common to hear building owners state that building green cost up to 10% more than traditional methods. Today, we are seeing evidence that initial costs for green building can be equal to or lower than traditional designs.
Additionally, companies are saving money by reducing energy as well as operating costs and they are building goodwill in the communities where they do business by considering their footprint.
Sustainable concrete
Globally estimated at 15 billion tons per year, concrete is the second most-used material (water being the first) and is used in virtually all construction projects. Like all building materials, concrete has a large footprint, but one that can be reduced providing valuable, sustainable benefits in return.
Durability is inherent in the concept of sustainability. Concrete is the most durable building material—a claim no other product can make. Concrete also can contribute to energy reductions, air quality improvements, waste reduction, and water quality and quantity improvements. For example, pervious concrete improves water quality and quantity by limiting the pollution that reaches waterways, recharges groundwater, and reduces the demand for stormwater runoff and treatment infrastructure. Similarly, a concrete floor slab installed as a structural element simply can be stained or polished for an attractive finished floor without the need for carpet, wood, or tile, all of which must be maintained and/or eventually replaced.
In terms of saving energy, concrete roadways are more sustainable than most simply due to reduced rolling resistance. Because of its lighter color and higher reflectivity, concrete pavements are safer to use at night and reduce the urban heat island effect. Using concrete walls for buildings and homes takes advantage of the thermal mass of concrete, lessening the temperature fluctuations inside the structure and the HVAC demands that follow.
Impact on the contractor
As mentioned earlier, LEED is a rating system that encourages behavioral changes in concert with sustainable construction and other green building practices. The concrete contractor needs to encourage designers, engineers, owners, and other members of the construction team to consider the benefits and behavioral advantages of concrete solutions.
The key is for the contractor to be involved in the integrated design concept, which is critical to optimal success. The integrated design concept calls for a synergy of collective knowledge in which all practices in the construction process are involved at the beginning of a building project. It is at this stage when the concrete contractor should be pitching the sustainability of concrete solutions.
For example, if a project has sensitive land use requirements, concrete contractors should emphasize how their product can work around these site limitations at the beginning of the project. A contractor who offers pervious paving solutions can help owners save money up front by noting that their product eliminates the need for a detention pond and therefore allows for a smaller lot size.
In addition to participating in integrated design, sustainable concrete solutions require contractors to expand their understanding.
One reason contractors shy away from sustainable construction practices may be additional paperwork. Evidence of improvements must be documented to comply with LEED and other rating systems. This paperwork obviously takes time, but comes with a few hassles as well. It can be labor intensive for a contractor to ensure the custody of the ingredients in the concrete mix. However, there is a learning curve to this protocol and as certain practices become commonplace, the effort to process the paperwork will likely reduce. Contractors also may incur additional costs with some green products until they become more readily available, but the additional savings of sustainable concrete solutions can help increase business and ensure satisfied customers.
The two most-requested LEED credits asked of concrete contractors are to use recycled content and locally available materials. Contractors can incorporate a custom-made mix including recycled supplementary cementitious materials such as slag, fly ash, and even recycled aggregates. The use of locally available materials minimizes emissions from transportation, reduces fuel expenses, and keeps project dollars within the local economy.
Sustainability at the jobsite
A key advantage of concrete is the limited waste at the jobsite. Concrete contractors can bring the necessary amount of product to the job without the scraps. New and improved forming techniques reduce material use and waste as well, even if the formwork is performed onsite. Modular projects such as concrete masonry and precast concrete limit site disturbance. Some contractors are even figuring out how to recycle leftover concrete.
New and improved release agents, curing compounds, and dust control practices can improve air and water quality at the jobsite. Volatile organic compounds in reduced amounts or nonexistent in many finishes, solvents, and release agents directly translates to improved health and safety of workers. In turn, there is reduced liability at the jobsite.
Contractors need to consider how to recycle the materials and equipment used throughout a project. Additionally, there is a push for vehicles powered by alternative fuels.
A future wild card is the issue of carbon trading or taxation. These refer to a fee applied (either through tax or free generated by market forces) for CO2 users. If these types of regulations are implemented in the near future, there will be an even greater incentive for companies to look for energy savings at the office and in field operations.
Right here, right now
Currently, sustainable construction still is considered new, and no national regulations or standards yet exist. Regulations typically are driven at the state or local level, and vary widely. There are some building blocks, such as ASHRAE SPC 189.1, on which broader standards will be built. Lacking a definitive standard, many states, municipalities, and businesses are adopting LEED. Nevertheless, LEED is a voluntary rating system by which to measure performance.
Sustainable construction is not just the responsible thing to do, it also can be the competitively advantageous thing to do. Several general contractors are establishing themselves as leaders and even using it as a marketing tool to generate business. Rick Fedrizzi, founding chairman of the USGBC, said green building demonstrates leadership and companies adopting sustainable construction practices are stepping across the line to make a difference.
This gets us back to the triple bottom line. Remember, in addition to an environmental and social benefit, there is an economic benefit. Contractors must recognize the biggest thing they have to offer is the multiple benefits concrete applications can contribute to sustainable development. However, these benefits mean nothing if the solutions are unknown. Integrated design requires contractors to offer ideas up front, not at the bid stage.
Invitations to the table require contractors to be educators. Develop the opportunities to get in front of colleagues, and bring in suppliers, local promotion partners, and others to get the word out. The industry is no longer looking at concrete as simply a slab to drive on, but what more it can do. General contractors, owners, and others are hungry for credible and helpful information. The industry can take this opportunity to share the facts about concrete benefits or let the competition tell their story.
David Shepherd, AIA, is director of sustainable development for the Portland Cement Association. He can be reached at [email protected] or 847-966-6200.
