Leadership in Energy and Environmental Design (LEED®) is a rating system devised by the United States Green Building Council (USGBC) to evaluate the environmental performance of a building and encourage market transformation towards sustainable design. The system is credit-based, allowing projects to earn points for environmentally beneficialstrategies taken during construction and use of a building. Leadership in Energy and Environmental Design was launched in an effort to develop a “consensus-based, market-driven rating system to accelerate the development and implementation of green building practices.
Why Use LEED?
LEED is a voluntary program; however, obtaining a LEED certification projects a positive environmental image to the community. Additionally, using many green building practices can result in energy and cost savings over the life of the structure. Other advantages include better indoor air quality and plenty of daylight. Studies have shown that workers in these environments have increased labor productivity, job retention, and days worked. These benefits contribute directly to a company’s profits because salaries—which are about ten times higher than rent, utilities, and maintenance combined—are the largest expense for most companies occupying office space. In addition, students in these environments have higher test scores and lower absenteeism. Retail sales are higher in daylit buildings.
Who Uses LEED?
According to the USGBC, over 20,000 projects comprising 2.8 billion square feet of commercial real estate have been certified as of January, 2014. Approximately 10 percent of these are federal or state properties. LEED for Homes currently has over 50,000 dwelling units certified and an additional 82,000 registered. Support for green buildings has increased rapidly each year over the past decade.
There are currently five versions of LEED: Building Design and Construction (BD+C); Interior Design and Construction (ID+C); Building Operations and Maintenance (O+M); Neighborhood Development (ND), and Homes.
Detailed information on the LEED programs and project certification process is available from USGBC at http://www.usgbc.org/. The site outlines the intent, requirements, technologies, and strategies for meeting each credit. Credits are broken down into individual points. A building requires at least 40 points for certification in LEED 2009 for Building Design and Construction. Silver, gold, and platinum levels are also available.
LEED v4 offers similar strategies and is currently in a pilot phase. Project users will have the option of choosing LEED 2009 or LEED v4 until October, 2016, when LEED 2009 will be closed.
LEED 2009 Certification Levels
- Certified, 40 - 49 Points
- Silver, 50 - 59 Points
- Gold, 60 - 79 Points
- Platinum, 80 points and above
Requirements for complying with prerequisites and credits in LEED v4 are detailed in a comprehensive user's manual, U.S. Green Building Council (USGBC), 2013. Reference Guide for Building Design and Construction v4.
How Can Concrete Contribute to Points?
Concrete's characteristics of low albedo, thermal mass, recyclability, local availability, lack of volatile organic compounds (VOCs) and the industry's transparency can all contribute to more-sustainable projects. PCA's
Concrete Contributions to LEED v4, focuses on how concrete can contribute credits in LEED v4 for Building Design and Construction (BD+C), which includes New Construction, Core & Shell, Schools, Retail, Data Center, Warehouses and Distribution Centers, Hospitality, and Healthcare.
Concrete building materials contribute to a wide range of environmental strategies and LEED credits:
- Within sustainable sites, pervious concrete paving and paver systems are used for rainwater management;
- The light color of traditional concrete contributes to a reduction in urban heat island impacts;
- Cement can be used as a solidification and stabilization medium for contaminated soils on brownfield redevelopment;
- The energy and atmosphere credits seek to reduce operational energy of the project.
There are a variety of insulated concrete wall systems that incorporate high levels of insulation, minimize or eliminate air infiltration and provide thermal mass;
- Material and resources credits are offered for impact reductions in the construction materials from which the building is made. Concrete is very durable, lasting much longer than most building materials in similar conditions. Credits for building reuse, recycled content, and regionally available materials are supported by concrete applications.
For more in-depth information, see the NRMCA Concrete Use and Sustainability Report, Concrete's Contribution to LEED 2009.
Concrete, The Choice for Sustainable Design, 443
Concrete's Contribution to Sustainable Development, (2008), E. Ashley, L. Liomel, The Journal of Green Building, Volume 3, Number 4 Fall 2008, 15 pages.
As a result of its versatility, beauty, strength,·and durability, concrete is used in most types of construction, including homes, buildings, roads, bridges, airports, subways, and water resource structures. And with today's heightened awareness and demand for sustainable construction, concrete performs well when compared to other building materials. The production of concrete is resource efficient and the ingredients require little processing. PDF.
Contributions to LEED v4, (2013), Portland Cement Association
This technical brief summarizes the credit contributions in LEEDv4 for concrete and concrete products. PDF.
Energy Efficient – The Mass of Concrete Construction
Environmental and Cost Benefits of High Albedo Concrete
High-gloss Finishes, Creating New Floors with Polished Concrete, (2007), H. Jancy, and G. Schwietz, The Construction Specifier magazine, Construction Specifications Institute, 8 pages.
Polished concrete can be used to refurbish old or damaged floors or add dimension to new ones. The process to attain glossy surfaces is discussed, along with safety standards, maintenance, and chemical treatments to protect floors. This discussion also includes an overview of materials used to color concrete surfaces to add a further decorative element. PDF.
IPS guide reprint 2014
LEED Reference Guide, (2010) Updated Third Edition with LEED 2009 Information, RMC Research & Education Foundation, PCA, and National Ready Mixed Concrete Industry, (2005-2010), 85 pages
This invaluable reference manual for architects, specifiers, contractors and building owners will guide the user through the steps to achieve LEED NC v 3.0 credits using ready mix concrete materials. Strategies, examples and detailed instructions help users understand how concrete can contribute to urban heat island reduction, energy savings, storm water quality and quantity, recycled content and local availability credit. PDF.
Phoenix-Award Winning Kendall Square Rises from Cement-Treated Brownfield Site, C. Carleo, T. Clark, and C. Wilk, (2006), 2 pages
The Kendall Square Redevelopment project in Cambridge, Massachusetts, was named the Grand Prize winner of the ten regional Phoenix Award winners at the EPA-sponsored Brownfields 2006 Conference. As a former location of a manufactured gas plant, property soil was impacted with coal tar to a depth of over 20 feet. The property was remediated using cement-based insitu solidification/stabilization treatment. The Phoenix AwardsTM is considered the pinnacle of achievement of excellence in brownfield redevelopment and often is called the brownfields’ equivalent of Hollywood’s Oscars. The remediated property is now the site of a Leadership in Energy and Environmental Design (LEEDTM) Platinum-certified office building. PDF.
Polished Concrete Can Be Green, (2007), L&M Concrete News, 3 pages.
A durable, long lasting, attractive polished concrete floor is a value-loaded option within the reach of almost any facility today.
Recommendations for Integrating Functional Resilience into LEED Programs
Recommended Revisions to LEED for Homes
Recommended Revisions to LEED NC and CS
SN2982-Solar Reflectanceof of Concrete for LEED Sustainable Sites Credit-Heat Island Effect
SN2982a-Solar Reflectance Values of Concrete
The Engineering Guide to LEED - New Construction: Sustainable Construction for Engineers, (2008), L. Haselbach, What is the solar reflectance of roller-compacted concrete?
The Engineering Guide to LEED-New Construction is a unique new resource that gives the reader a solid understanding of the U.S. Green Building Council's LEED-NC rating system, while also offering a practical text for use in real world applications. Haselbach, LEED-accredited engineer and professor at the University of South Carolina, begins with an introduction to sustainable construction and the USGBC LEED-New Construction rating system. She then delves into the specific prerequisites and credits used for LEED certification. Finally, several examples of sustainable construction within specific sectors such as the military are presented, indoor air quality discussed, and the integration of stormwater management into the LEED process explained. Exercises in the chapters help to reinforce one’s understanding of the LEED system and calculations. Ample references are supplied for further study. Available on Amazon.com.