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LEED 2009

The essence of the menu-based system does not change with LEED 2009. What does change, however, is a weighting of the points based on a series of high-priority environmental and human health issues, such as resource depletion, water intake, and indoor environmental quality. The two main issues that surfaced to the top during the USGBC's extensive life-cycle assessment analysis process were climate change and energy efficiency.

In order to accommodate this weighted revision, the possible points available will increase. For LEED-NC, for example, the maximum point count increases to 110 (100 plus 10 bonus points) from the 69 previously available.

Comparing LEED-NC 2009 to the existing LEED-NC version, water efficiency will contribute to 10 percent of the points instead of 7 percent, energy 35 percent instead of 25 percent, and transportation 17 percent instead of 7 percent.

For green building designers, the impact of these changes will be revealed once projects start to incorporate LEED in mid-2009.

Aside from the environmental and health benefits sought through the update, this is a good change for building owners, I believe, as well as taxpayers who have a LEED requirement for public buildings in their state or city. Energy-efficient buildings offer financial benefits to their owners in the long term, and LEED projects will have to include more energy-efficiency measures in order to get the level of certification the designers are seeking.

I also expect this same benefit will make it easier for designers to sell LEED projects to uncertain clients, particularly in this hard economic climate.

Generally, the credit content has not changed much in LEED 2009. The baseline water efficiency level in the old version of 20 percent is now a prerequisite requirement, which makes a great deal of sense. Most projects achieve the 20-percent water savings easily, at no additional cost to a project, with the use of readily available low-flow fixtures. Now project teams can be rewarded for going further and achieving savings of 30 and 40 percent.

Beyond LEED 2009

So with only minor changes to the actual credit content, have the concerns about LEED been sufficiently addressed?

One of those criticisms has been that LEED does not adequately address regional variation. For example, issues of humidity and natural cooling are different in different climates. LEED 2009 takes a step to address this. Four new points will be tailored to regional issues. These credits are being determined by each regional USGBC chapter and have not yet been released.

LEED v3 also takes some additional steps that should encourage historic preservation, such as by giving additional points for locating buildings in dense communities.

Another significant change that may encourage reuse of existing buildings is a new Alternate Compliance Path entitled "Life Cycle Assessment for Building Assemblies," which can be used to determine a project's materials and resources credits. This performance-based path uses a new Life Cycle Assessment credit calculator — currently in beta testing and available for project teams to try out — to take into account the embodied energy and lifespan of existing building materials.

This also seems like a step to move LEED closer to a performance-based system and away from the current system, which is based on design and construction requirements and benchmarks rather than performance.

The green building community would also like to see LEED encourage affordable housing and accessibility in the same way it has driven the market for green products and materials. Issues of social equity are not being addressed in this LEED update, but rumor has it that this kind of change is being evaluated now by the USGBC in time for the 2011 LEED version.

LEED will now be revised every two years, with major credit content changes expected in 2011. Additionally, it is anticipated that these credits will be weighted according to new social and cultural criteria that are just beginning to be developed.

LEED 2009 is a great step in the right direction, offering a transitional stage between the existing system and the further-improved system we should see emerge in 2011. Incorporating social equity will be no small task — but there's no triple bottom line without it.

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Amanda Sturgeon, AIA, LEED AP, is a senior associate at Perkins + Will and is codirector of the firm's national sustainable design initiative. Based in the Seattle, Washington, office, she has been leading sustainable design projects in the Pacific Northwest since she moved there in 1998.

The Dockside Green development in Victoria, British Columbia, received 63 points (of 69 possible) under the LEED-NC v2.2 standard, earning it Platinum certification. Photo: Enrico Dagostini Extra Large Image The LEED-NC v3 rating system now has 110 possible points. Image: Courtesy USGBC Extra Large Image Public transportation access is more heavily weighted in the new LEED 2009 standard. Photo: Payton Chung Extra Large Image Disconnected, car-centered suburban buildings may receive a smaller share of the 26 points now possible in the Sustainable Sites category of LEED v3 than they would have in previous LEED versions. Photo: David Owen/ Artifice Images Extra Large Image Under the LEED 2009 site-selection criteria, points are given to building sites, like that of Milwaukee's Urban Ecology Center, that increase building density and connection with an established community. Photo: Kevin Matthews/ Artifice Images Electricity used in buildings accounts for about three-quarters of electricity used in the United States. LEED 2009 encourages greater energy efficiency. Image: Courtesy Mazria Inc. Dual-flush toilets can increase building water efficiency, a goal further encouraged by the new LEED standards. Photo: Jeff Tolentino Extra Large Image SUBSCRIPTION SAMPLE Starting with LEED v3, a special category of points will be awarded for region-specific building responses, still being determined by the regional USGBC chapters. Photo: Chris Cooper   Click on thumbnail images to view full-size pictures.