This is a time of massive and rapid change in the environmental practices of the U.S. building industry. Green buildings are a focal point and a catalyst for these changes. Green technologies are evolving rapidly, leading to both improved cost effectiveness of green development strategies and increased acceptance of green building concepts in mainstream projects. At the same time, the speed of this evolution is creating a need for increasing levels of rigor and sophistication in the green building rating systems, such as Leadership in Energy and Environmental Design (LEED™), used to evaluate those strategies.

A parallel development that will become even more significant in the future is the realization that the organizations that build and operate green buildings must change to achieve the desired results. Organizations must become more sustainable — “greener” organizations — in which their green buildings are just one component of an overall corporate sustainability strategy, if they are to have the maximum impact (see discussion below regarding LEED for Existing Buildings).

Figure 1. “S-Curve” of Technology Evolution

It’s remarkable how quickly the U.S. Green Building Council’s (USGBC) LEED rating system has become a major factor. From its introduction three years ago, LEED has risen to its current position of standard practice for the Federal government (and for many state and local agencies) and rapidly spreading to private sector applications. How this is happening is instructive: the course of market adoption of any new technology over time typically follows the type of curve shown in Figure 1.

Figure 2. Phases of Technology Evolution

If one examines this curve in more detail, one sees the phases of development shown in Figure 2. Innovators introduce a technology, early adopters multiply its use, then there is a transition as the mainstream accepts it and it ultimately reaches maturity.

Figure 3. LEED Evolution of Various Market Sectors

At present, LEED probably could be characterized as being in transition from the “early adopters” stage to the transition toward becoming mainstream. Portions of the real estate industry are entering the steep vertical “transition” part of the curve, while others are still in the early adoption stage.

LEED-registered projects currently represent close to 5 percent of the total square footage in U.S. new construction. Because the ultimate target is approximately 25 percent of the entire market, these results are substantial. Five percent is often considered a crucial milestone in the transition to market adoption. The mainstream is beginning to accept the rating system, but for the majority, LEED is still an innovation they’re learning about and just starting to embrace. This breaks down as shown in the table below (Figure 3).

The reality is that with fewer than 60 projects certified by LEED to-date (that is, that have completed construction and the LEED documentation submittal and acceptance process), the program is still in its infancy. Yet with 841 projects (as of June 1, with more every week) registered under LEED and moving through the pipeline, major changes and impacts are being achieved as the industry deals with these projects. As LEED finds its way into new sectors of the facilities world, new challenges and demands are being placed on LEED to accommodate the specifics of these new sectors.

Different participants and market segments perceive LEED differently, and as a result, have different expectations for its development and evolution. For people just beginning to learn and use LEED, there is no apparent need to change its requirements. In fact, keeping it the same and even simplifying it will help make it more accessible to these market segments. Yet for those designers, contractors and owners who are now experienced with LEED and have developed increasing sophistication with sustainable design, there is a perceived need to see LEED further evolve. As LEED approaches the transition in some markets where it will soon be considered mainstream, it must evolve. This is also an outgrowth of the rapidly improving availability of green materials and methods: it is now possible to achieve much more with green materials than was economically feasible when LEED 2.0 was written.

These differing expectations are creating challenges for the USGBC in its role as the developer and purveyor of LEED. The USGBC is working hard to simultaneously:

•bring more projects into LEED

•train more of the building industry on how to use LEED

•develop new LEED products to cover new building types

•upgrade the existing LEED products to reflect changes in technologies and emerging knowledge

The challenge LEED faces is to bring along the newcomers—who have yet to even try its original format, while also evolving LEED to meet the needs of more advanced practitioners. As the market grows, we need to support the newcomers and to support new sectors of building types. Moreover, as the technologies and our knowledge move ahead, LEED will need to reflect those changes. To further complicate the situation, it takes a minimum of two to three years to develop a major new version of LEED. To maintain the appropriate level of rigor we can’t move too fast; yet we must increase our speed!

LEED Products for Different Markets

Figure 4. LEED products being developed.

The way that these multiple objectives are being handled by LEED is as follows (see also Figure 4):

The current LEED for New Construction (LEED-NC, Version 2) is periodically updated through minor version changes. After the initial publication of Version 2.0 in April 2001, Version 2.1 was issued in November 2002 and Version 2.2 is currently in development.

These versions are intended to address specific bugs and anomalies that have been found in the rating system, without changing the underlying concepts and rigor of the requirements.

Meanwhile, a new version 3.0 of LEED-NC is now being developed which will change the content and rigor, so as to address the need for “raising the bar” in response to improvements in technologies, knowledge, data and market advancement. This is scheduled to be released in 2005.

LEED for Commercial Interiors (LEED-CI) was published in draft form in early 2002 and is now being tried on a pilot basis by 52 projects. The target for release of the Version 2 LEED-CI is mid-2004. The target market for this LEED product is the interior improvements of buildings, where the Tenant Improvements are done separately from the shell building, and where the shell building could either be LEED-rated or not.

LEED for Existing Buildings (LEED-EB)was published in draft form in January 2002 and is now being tried on a pilot basis by 76 projects. The target date for release of the Version 2 LEED-EB is October 2003. The target market for this LEED product is the huge inventory of existing buildings, which, by number of projects, is roughly eighty (80) times the size of the new construction market! It provides a framework for examining and improving the sustainable operations of existing buildings, even recognizing that the basis building design, materials, and systems cannot be changed.

LEED for Core & Shell (LEED-CS) is currently in development. It is intended to apply to the design and construction of new buildings in which only the core and shell is governed by the original design (as opposed to the entire building fit-out). As such, it provides a natural complement to LEED-CI, which applies to the fit-out and not the core-and-shell. The target date for release of the LEED-CS is early 2004.

LEED for Homes is currently in development. It is intended to apply to the design and construction of new low-rise residential buildings. It is being designed to complement existing green builder programs that already exist in many areas of the country. It is hoped that the draft of LEED for Homes will be available by late 2004.

Evolving Technical Rigor of LEED

Figure 5. LEED’s Role in Market.

LEED is a driver of environmental and technical excellence in buildings. The mainstream (maybe 75 percent of the market) follow green practices that will be influenced by, but not necessarily qualify for, LEED certification. In fact, the US Green Building Council aims to have only about 25 percent of the market actually participate in the LEED rating process. This advanced market segment of high performance buildings, certified by LEED, will help raise the bar for the entire design and building industry, thus helping transform the entire market (see Figure 5).

Figure 6. Increasing Rigor Maintains Validity of LEED Levels.

As practices and markets become more advanced, what is innovative today will be considered much less sophisticated tomorrow and even “behind the curve” in perhaps five or 10 years. Rather than let a Platinum (LEED’s highest) rating become easily attainable by any project as technologies improve and the industry’s proficiency increases, LEED must continue to raise the bar to keep moving toward a more sustainable future. Thus, for a given level of sustainability as measured by LEED, the level of rigor will increase over time to reflect progress in technologies and practices, as illustrated in Figures 6 and 7 (previous page).

New Metrics for Sustainability

Figure 7. Increasing Rigor Maintains Validity of LEED Levels.

Continued evolution to higher levels of rigor likely will include more sophisticated metrics. For example, the credits now earned for environmentally preferred materials (and potentially other credits as well) may be determined at least conceptually by a Life Cycle Assessment (See Figure 8).

Figure 8. Product Life Cycle

This would encourage builders to consider the environmental impact of the origin, manufacture, transportation, installation, usage, disposal and recycling of building materials. In the future, it is also likely that carbon emissions will be used as a means to assess LEED Energy credits. Both these measures will require much more detailed and rigorous data from manufacturers, so that designers and owners can make informed decisions about products and systems. For example, very little data exists at present to enable LCA evaluation for most materials and products in the U.S. — hence, the USGBC’s support of research efforts to increase the availability of such data. Until such data are widely available, LEED will need to strike a balance of the latest technical data and various other market considerations in its decision-making and balloting processes.

Looking at the entire life cycle of a building also will bring more emphasis on the operations of buildings. Full LCA of building designs conducted in other countries reveals that 80 to 90 percent of life cycle impacts arise from the operational phase. In the best buildings, the proportion of operations-related impacts is lowest. Discussion of this approach includes ISO 14001 as a possible process tool for evaluating the environmental impact of a building’s ongoing operations. For example, IS0 14001 calls for developing an Environmental Monitoring System (EMS) for the facility or organization. This provides a means for delegating responsibility to ensure the building design achieves its intended goal over time. As a result, efforts toward improving sustainability could be recognized and institutionalized throughout the organization, with assurance that actual sustainable operations will be achieved. Organizations already certified under ISO 14001 can use it as a framework for making building design decisions. Organizations without ISO 14001 certification can implement it as part of a building project to capture the benefits and knowledge from the green building process.

However, ISO 14001 gives no specific methods or criteria for measuring the environmental impacts from buildings so there are a number of potential synergies between the ISO 14001 Environmental Management System (“EMS”) and LEED. For new construction, getting LEED-certified can position the building to seamlessly feed data into an EMS for the Monitoring & Verification credit. Implementing an EMS can educate and inform stakeholders about green building efforts. In an existing building, the EMS can form part of the LEED-EB (LEED for Existing Buildings) operations program. LEED EB is designed to integrate effectively within an ISO 14001 framework.

As noted above, technological evolution underpins the entire green building concept. The results to date have been encouraging. Materials containing recycled content (like fly-ash concrete, drywall and metals) have become more easily and cheaply available. Low emissions products of all types (paints, sealants, adhesives, carpets, fabrics, etc) are now readily available as a standard specification choice. High performance systems such as underfloor air distribution and daylighting now are routinely considered if not regularly adopted. Water conservation and efficiency trends have made the use of reclaimed water and high efficiency plumbing fixtures more commonplace. Construction waste management has turned recycling into a revenue stream for the project instead of an added cost.

The future holds just as much promise. Strides in distributed generation are moving toward the concept of every building becoming an energy producer. Integrated renewable energy systems such as photovoltaic solar (PV) increasingly will become part of the architecture. The use of bio-mimicry to adapt life-supporting natural processes to the manufacturing of materials could lead to non-toxic materials that are also higher performance and lower cost. Improved bar coding could put Material Safety Data Sheet (MSDS) information about environmental performance right on the products themselves.

Regenerative systems can ensure the environment is actually improved by the building. Fully intelligent buildings and monitoring and verification functions will “talk” to users to ensure environmentally optimized operation. The challenge, of course, will be to develop systems that are simple to implement and commission so they will remain in long-term operation.

Conclusions

The real estate industry is going through a profound and unprecedented change in the design and development of green buildings. The LEED rating system has been the catalyst for this change. LEED’s success has created an increasing set of pressures for it to grow and evolve to meet a wide variety of industry needs and expectations. At the same time, the rapid changes in technologies and industry practices are forcing technical changes in LEED. There are many new initiatives underway within the USGBC to respond to these opportunities, including the development of new LEED programs and the evolution of the underlying means of measuring sustainability. The future promises even more progress and opportunity to move the real estate industry toward a more sustainable future.

NOTE: The opinions expressed here are those of the authors and do not necessarily represent the official position of the US Green Building Council on all points contained in this article. The USGBC can be reached at info@usgbc.org or 208-828-7422. Malcolm Lewis of CTG Energetics can be reached at MLewis@CTGEnergetics.com or 949-790-0010.