November/December 2009
Executive Director's Corner
C O N T E N T S
Homes: Greening the MLS, By Glen Girard, USGBC CO Communications Chair
Project Highlight: Housing Resources Office Building Achieves LEED Certification- First Existing Building to Achieve Certification in Grand Junction, By Elaine Matthews, Ryan, Sawyer & Associates
REGREEN: Workshop October 28-29, taught by Annette Stelmack and Pete Yost
Membership: Recap of Our 2010 Annual Membership Event, By Barb Josey, USGBC CO Membership Chair
Colorado Building Green is the official newsletter of the U.S. Green Building Council – Colorado Chapter, and is published bi-monthly. If you are interested in submiting a story, ideas or other information for publication, please contact the editor at sarah@usgbccolorado.org
LEED Buildings and Energy Efficiency: Are Intentions Good Enough?
By Mark Stetz, P.E. CMPV, Principal of Stetz Consulting LLC
In an attempt to address some of the weaknesses with LEED 2.2, LEED 3.0 – released April 2009 – further emphasizes designing for and achieving energy reductions. The point system has been revamped to make it align more with the USGBC’s goals of energy and carbon reductions. Energy efficiency (EA-1) can now earn a building up to 19 points and the Measurement &Verification credit (EA-5) – which validates energy use - is now worth 3 points. To enable additional post-evaluation research, USGBC will require post-occupancy access to the water and energy bills, access that needs to be maintained even if the building changes owners. Although some critics have suggested that certification be revoked if an individual building ever fails to live up to its claims [4], the USGBC has not yet taken that draconian step.
Lessons learned from studying existing buildings – LEED and non-LEED alike – support the continued integration and cooperation of disciplines when designing, constructing, and commissioning buildings so that they work as a system rather than a collection of parts. They also show that performance monitoring during the life of the building is equally important. Only 25% of LEED-certified buildings apply for and receive the M&V Credit EA-5 [5], possibly because there are easier and cheaper ways of earning points. Unfortunately, receiving the M&V credit only requires writing an M&V plan; there is no requirement that it be implemented. The expectation that someone will carry out the M&V plan will continue to be a weakness with the LEED system.
Benefits of building performance monitoring include not just cost control and the ability to claim carbon emissions, but also feedback for the designers and operators to apply to their next project. Building simulation models may appear reliable because they are done on a computer, but many building characteristics are unknown and unknowable, so assumptions are used instead. For example, a building may be designed as a 9 to 5 office building but the tenants actually operate 24/7. The resultant energy use will be significantly greater than originally estimated, but with no real verification, it would appear that the building is less efficient than intended. In this case, the assumed occupant behavior does not match reality. Only by verifying the actual energy use and comparing it to the models can assumptions and building performance can be validated.
If LEED-certified buildings are to live up to their expectations, performance cannot be based on design intent. Hope is not a plan. The goals of energy, cost, water, and carbon reductions need to be demonstrated in practice if the LEED program is to maintain credibility. The new LEED 3.0 requirements are a step in the right direction; the rest is up to those who design, build, commission, and occupy buildings.
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