The Leadership in Energy and Environmental Design (LEED) Green Building Rating System continues to enjoy remarkable growth as the building industry seeks to use its concepts and technical criteria to transform the built environment. As of Sept. 1, LEED certification has been sought for more than 14,000 individual commercial projects totaling almost 4 billion sq ft, with dozens more joining the ranks every day. Believing that incremental change to the functions of the LEED rating system will not be enough to keep up with global warming and climate change, the U.S. Green Building Council (USGBC) recently introduced LEED 2009.

The need to continue to strike the optimal balance between market uptake and technical advancement is one of the driving forces behind LEED 2009. A concerted effort has been made to ensure that it capitalizes on existing market momentum.


LEED 2009 represents a reorganization of the LEED rating systems for commercial buildings combined with a series of major technical advancements focused on improving energy efficiency, reducing carbon emissions, and addressing other environmental and human-health outcomes. LEED 2009, along with an expanded third-party certification program and significant enhancements to LEED-Online, make up a multifaceted initiative referred to as LEED Version 3.0.

“LEED Version 3.0 will build speed, scale, and capacity into all aspects of LEED, allowing USGBC to deliver a tool that will help us achieve green buildings for everyone within a generation,” Rick Fedrizzi, president, chief executive officer, and founding chair of the USGBC, said.

The LEED rating system defines a consensus metric for leadership in green building that forms a basis for continuous improvement. The evolution of LEED is based on technical, scientific, and market-based advancements.

Two years in the making, LEED Version 3.0 is the response to user and USGBC-member requests for a rating system that is more flexible and adaptive. It solidifies LEED's technical rigor and consensus-based integrity without sacrificing its ability to balance environmental excellence and the business realities of the building industry.

LEED 2009

LEED 2009 builds on the fundamental structure and familiarity of the existing rating system, but provides a pathway for more readily incorporating new technology, processes, and protocols. Projects will have the option of being upgraded to LEED 2009 when the new rating system launches via LEED-Online.

“Continuing to seek the right balance between technical advancement and market transformation was a driving force behind the LEED 2009 work,” Scot Horst, chairman of the volunteer LEED Steering Committee (LSC), which leads the technical development of the LEED rating system, explained. “The ‘big ideas’ we've proposed include transparent weightings of LEED credits so the highest-priority credits achieve the most points, a new mechanism for incorporating bioregional credits, and a more nimble framework that supports rapid response to emerging environmental and human-health issues.” (Figure 1)

The public-comment period is a critical part of the consensus process by which the LEED rating system is developed. During this period, stakeholders are invited to review all of the proposed improvements and offer technical or market-oriented perspectives. All of the public comments are reviewed by the USGBC volunteer committees that oversee the LEED rating system. The USGBC responds to all of the comments and posts the comments and responses (without the names or organizations of those commenting) on the USGBC Website (

LEED 2009's first and second public-comment periods brought thousands of comments. Unless a third public-comment period is required, the new rating system will go to USGBC member ballot this fall, with an anticipated launch date of January 2009.


“Mitigating climate change is our top priority institutionally, so the highest weightings were given to those building practices that improve energy efficiency and thereby reduce CO2 emissions,” Horst said.

To help define what those weightings should be, the LSC and its committees created a tool that ranked the relative importance of building impacts on the environment and building occupants. They then looked at the contribution of building-related functions (e.g., the consumption of energy by building systems or water use) to impact categories by evaluating the group of rating-system credits associated with those functions and applied that ranking to the scorecard. By comparing the two rankings, they could decide whether a credit contributed to an impact category by mitigating a negative environmental or human-health issue or promoting positive outcomes. Think of it as a big game of Sudoku. In this case, the goal is to specify credit weights that sum to 100 points in each impact category and multiply across to a reasonable weight for individual credits.

“Two things will help make this clearer,” Horst said, “analyzing the sample scorecards that were part of the public-comment documents and reviewing the tool to help to understand the impacts of various decisions they might make for a specific building.”


Currently, all LEED project submissions are reviewed by the USGBC with the support of independently contracted reviewers. Beginning in January 2009, the USGBC will move administration of the LEED certification process to the Green Building Certification Institute (GBCI), a non-profit organization established in 2007 with the support of the USGBC. Working with the selected certification bodies, the GBCI will deliver a substantially improved, International Organization for Standardization- (ISO-) compliant certification process that will be able to grow with the green-building movement.

“Moving the administration of LEED certification under GBCI will continue to support market transformation by delivering auditable third-party certification. Importantly, it also allows USGBC to stick to the knitting of advancing the technical and scientific basis of LEED,” Chris Smith, USGBC chief operating officer, said.

As part of the move to GBCI, building-certification review will move from independent contractors to a group of certification bodies with deep experience in high-level certification processes:

Of particular concern to hopeful LEED Accredited Professionals (APs) is how LEED 2009 will affect the LEED AP exam. While the current version of the exam will be available through 2008, it will be updated after the new certification program launches.

Even as LEED 2009 proceeds through the public-comment and ballot phases, GBCI is working with volunteer subject-matter experts and exam-development consultants to evaluate the changes that will be needed. LEED AP exam workshops will have updated curriculum to reflect LEED 2009 beginning in November.


The LEED Version 3.0 update will include a comprehensive technology upgrade to LEED-Online aimed at improving user experience and expanding its portfolio-management capabilities. LEED-Online incorporates tools and applications that improve accuracy, data capture, collaboration, and convenience and provides context-sensitive help that paves the way for better decisions. A variety of software-application tools developed by third parties are being incorporated to augment information usability, acquisition, and storage.

Each credit category will have access to a reference tool that gives specific information on how to earn the credit. This tool will cost extra, but give in-depth information on how to execute specific strategies at the design phase, helping users identify best practices in green design.

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As vice president of LEED technical development for the U.S. Green Building Council, Brendan Owens, PE, LEED AP, collaborates with volunteer technical committees to refine the LEED Green Building Rating System. Currently focused on creating the framework for LEED Version 3.0, he has a bachelor's degree in engineering from Purdue University.