2013 changes to LEED credit ratings and requirements will include recycled content, regional materials zone definitions and environmental product declarations (EPDs).
By Claude Goguen, P.E., LEED AP
If you are a designer, specifier or regulator, chances are you have been involved in at least one LEED project. LEED stands for Leadership in Energy and Environmental Design and was developed by the U.S. Green Building Council (USGBC) in 2000. It provides building owners and operators with a framework for identifying and implementing practical and measurable green building design, construction, operations and maintenance solutions. Since its inception, the LEED green building program has been used to promote sustainable building, design, construction and operations practices. The current version is known as LEED 2009.
Changes in the new LEED v4
LEED v4 is the next version of the LEED program and will include the step in the continuous improvement process and the ongoing development cycle of the LEED program, including the Building Design + Construction, Interior Design + Construction, Operations + Maintenance, Neighborhood Development, and LEED for Home Rating Systems. LEED v4 will be more globally aligned with international standards to make it more applicable for LEED projects outside of the United States.
LEED v4 offers increased technical rigor, expands the market sectors able to use LEED and strives for simplicity in terms of usability. The differences between LEED 2009 and LEED v4 are seen in three main areas:
1. New market sectors. New definitions affect data centers, warehouses and distribution centers, hospitality, existing schools, existing retail, and LEED for Homes Mid-Rise.
2. Changes to technical content. Stakeholder input will increase the technical rigor of the rating system. The proposed technical changes have been informed by market data, stakeholder generated ideas, expert engagement, and advances in technology and market acceptability of LEED and green building practices.
3. Revised credit weightings. Revised point distribution will more closely tie the rating system requirements to the priorities articulated by the USGBC community.
There are new prerequisites and credits across the LEED credit categories and rating systems. Point values have also changed. Each rating system has gone through a weighting process and has LEED points associated with each credit and option of the rating system.
How does LEED v4 affect the use of precast concrete?
Some of the changes affecting the use of precast concrete include:
• Site Development – Protect or Restore Habitat. (Formerly SS 5.1) Precast will still contribute in this category, because it’s made to order, reduces storage space on site and minimizes site disturbance.
• Rainwater Management. (Combined former 6.1, “Stormwater Design – Quality Control,” and 6.2, “Stormwater Design – Quantity Control”) Precast will still contribute through the use of stormwater products.
• Heat Island Reduction – Combined Heat Island Effect – Non-roof with Heat Island Effect – Roof. (Renamed “Heat Island Reduction”) Architectural precast concrete with an SRI1 of at least 29 will qualify.
• Environmentally Preferable Products and Materials, Prescriptive Attributes. (New credit for 2013) The former regional requirement will be replaced with the new “Support Local Economy” attribute. Recycled content (50% of total material cost), which currently applies to structure and enclosure, will apply only to non-structural elements.
• Regional Materials. “Regional” definition will no longer be 500 miles. It is currently based on “Regional Core Based Statistical Area” updated Dec. 1, 2009, by the U.S. Office of Management and Budget.
• Thermal Comfort. (Renamed from “Controllability of Systems – Thermal Comfort,” combined with “Thermal Comfort – Design Requirements for Achievement”) Design of heating, ventilation and air conditioning (HVAC) systems and the building envelope will need to meet the requirements of ASHRAE2 Standard 55-2010, “Thermal Comfort Conditions for Human Occupancy.”
• Precast Concrete Shell. Precast enclosure will contribute to LEED design due to thermal mass properties.
Current status of LEED v4
The LEED v4 fourth public comment period was open from May 11 to May 28. A number of key changes have been made to address the technical and market issues voiced throughout the course of previous comment periods.
Projects currently registered with LEED should follow the version under which they are currently registered. Project teams will not be able to register for LEED v4 until it has undergone a ballot vote by USGBC membership and is officially launched.
Due to overwhelming feedback from stakeholders, the USGBC recently announced that it will delay balloting on LEED v4 until June 1, 2013. As a result, changes may be made that will impact our industry. NPCA will continue to stay on top of any developments and will publish updates as they occur.
1 Solar Reflectance Index
2 American Society of Heating, Refrigerating and Air-Conditioning Engineers Inc.
For questions about this article, please contact Claude Goguen, director of Technical Services, at (317) 571-9500 or [email protected].