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LEED 2012 Released by U.S. Green Building Council for comment

Date: November 24, 2010

On November 8, 2010, the U.S. Green Building Council (USGBC) released for public comment a draft of the next version of the LEED rating systems. Among the USGBC's stated goals for the next version of LEED are the following:

  • Increase emphasis on integrated process and building performance
  • Harmonize inefficient duplication of LEED credits
  • Streamline project team engagement with LEED

USGBC observes that the release of high-performance green building codes is "clear evidence" that the market has transformed since the last LEED update. The increased emphasis on integrated process and building performance will primarily be achieved by updating the LEED credit category structure.

USGBC stresses that, because it is critical that stakeholders participate in the evolution of LEED, USGBC will begin, this month, a "stakeholder engagement" that will include multiple public comment periods open to all LEED stakeholders. According to the USGBC website, the first public comment period is open from November 8 through December 31, 2010, and a second public comment period is expected to run from July 1 through August 15, 2011. The projected date for the release of the new version of the rating system is November 7, 2012. As the current version of the LEED rating systems is denominated LEED 2009, this draft version has been named, at least for the nonce, LEED 2012.

USGBC summarizes the process and the goal as follows: "[W]e are embarking on a process of stakeholder engagement and careful development of a consensus-based, technically improved, and innovative rating system that continues to push the market toward optimal building design, construction, and operations practice."

LEED 2012: A Selection of Proposed Changes and Additions (LEED-NC)

The following is a brief selection of some proposed changes and additions set forth in LEED-NC 2012.

New Integrated Process (IP)

The intent of this credit is stated as follows: "Develop an early understanding of the relationships between technical systems, natural systems and occupants within a building project, its site, its context, and its intended use. Engage all key project team members for the purpose of making cost- and environmentally-effective integrated decisions throughout the design and construction process." This credit essentially takes the integrated project delivery method, with its team-based approach, and incorporates it into a LEED rating system credit. In order to optimize the stated project results, the project team analyzes and identifies interactions and synergies among systems and strategies throughout the design and construction process.

New Location and Transportation (LT)

The new LT category is largely a recycled and enlarged version of credits from the old Sustainable Sites category. Bicycle Storage is a LT prerequisite. The old Public Transportation Access credit has been rewritten as a new credit for Reduced Automobile Dependence. The two options for the credit include Transit-Served Location and a new Metropolitan Planning Organization Location with Low VMT (vehicle miles traveled).

Walkable Streets is a new LT credit. There are a number of required features, including, among others, the following: "principal functional entry" on the front façade must face a public space (not a parking lot), and continuous sidewalks or equivalent all-weather provisions for walking on the project site must serve all building entrances and connect them with public sidewalks.

Sustainable Sites (SS)

The Heat Island Reduction credit, which is two credits--roof and non-roof--in LEED 2009, is combined into one credit.

Water Efficiency (WE)

A new prerequisite is Landscape Water Use Reduction. All projects with a minimum of 1,000 square feet of exterior vegetated surface area are required to reduce irrigation water to or below a 30% baseline as established by the EPA's WaterSense Water Budget Tool.

Appliance and Process Water Use Reduction is another new prerequisite. Certain water-consuming appliances (residential and commercial clothes washers, residential dishwashers, and prerinse spray valves) and certain water-consuming processes (heat rejection and cooling, water temperature tempering, and Venturi-type flow-through vacuum generator or aspirators) must meet minimum performance requirements.

Another new WE credit is Cooling Tower Makeup Water. This credit has a number of requirements to conserve water used for cooling tower makeup while controlling microbes, corrosion, and scale in the condenser water system.

Energy and Atmosphere (EA)

A new EA credit is Demand Response, with the intent to "reduce regional carbon emissions and improve and enhance the optimization of electric generation, transmission and distribution resources." The options to attain this credit are as follows: (1) participate in a demand response program; or (2) implement permanent peak load shifting measures.

Materials and Resources (MR)

New MR prerequisites include Minimum Recycled Content and Construction and Demolition Waste Management Planning. A new MR credit is Whole Building Reuse, the intent of which is to "respect local landmarks and conserve material and cultural resources by encouraging the preservation and adaptive use of underused buildings." The options are as follows: (1) historic building reuse; or (2) renovation of abandoned or blighted building.

The Certified Wood credit of LEED 2012 is at this point a placeholder. The note to public commenters states as follows:

This requirement of LEED 2012 is a placeholder. Concurrent with the development of LEED 2012, USGBC is engaged in a reevaluation of the appropriateness of LEED's historic FSC (Forest Stewardship Council)-only policy related to certified forest products. The development of the Forest Certification Benchmark is, as of the release of the first public comment draft of LEED 2012, still ongoing and thus, the outcome is pending. USGBC action related to this vitally important but extraordinarily complicated issue will be complete prior to second public comment of LEED 2012. The second public comment draft of LEED 2012 will reflect the outcome of USGBC member ballot on this critical issue.

Indoor Environmental Quality (EQ)

The Construction Indoor Air Quality Management Plant--During Construction credit would become a prerequisite under LEED 2012. The new Low-Emitting Interiors credit combines the several Low-Emitting Materials credits in LEED 2009. The building interior is organized into five systems: flooring, ceiling, walls, thermal and acoustic insulation, and furniture.

The Daylight credit is recycled and simplified. The new calculation options are as follows: (1) Simulation -- Daylight Autonomy; (2) Simulation -- Illuminance Calculations; or (3) Measurement.

The EQ Daylight and Views credit would become Quality Views, with criteria to provide building occupants with prescribed lines-of-sight to the natural outdoor environment.

New Performance (PF)

While the Performance category is new, some of the credits are shifted from other categories. For instance, Fundamental Commissioning has been shifted from the EA category and renamed Fundamental Commissioning and Verification and contains enhanced requirements. Similarly, Enhanced Commissioning has been shifted for the EA category and contains more options and requirements.

A new prerequisite is Water Metering and Reporting, which requires that all water conveyed to the project, regardless of the source, must be metered. The intent of the prerequisite is to "promote water efficiency by providing accurate consumption data to building managers."

Another new prerequisite is Building-Level Energy Metering, which has the intent to [m]eter, track and share building-level resource use to encourage energy management and support LEED program evaluation."

A new credit is Reconcile Projected and Actual Energy Performance, the purpose of which is to "provide for the ongoing accountability of building energy consumption over time." This credit would require development and implementation of a measurement and verification program and a final report that, among other things, reconciles actual energy use with predicted energy use.

Please note that the above list is only a selection of proposed changes and additions to the LEED rating system. The reader is cordially invited to visit the USGBC website and review the entire proposed draft of LEED 2012.