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LEED Canada 2009 – Where are we now?

The LEED Green Building Rating System continues to evolve with the publication of the latest version, LEED Canada 2009 Building Design + Construction, last year. 


The LEED Green Building Rating System continues to evolve with the publication of the latest version, LEED Canada 2009 Building Design + Construction, last year. 

As a voluntary third-party rating system, LEED has been instrumental in transforming the industry toward sustainable development. The updated version does not significantly change the process used to implement the program or certify a building, but it does raise the baseline by which high performance buildings are measured; the same goals of recognition of achievement and market transformation are still firmly entrenched.

Generally, the rating system is more difficult than the earlier version, but the changes are still incremental rather than dramatically higher.  LEED 2009 rewards and responds to performance levels known to be achievable based on strategies that have been demonstrated or were lacking in certifications under version 1.0, a strategy that has proven to effectively create demand, forcing the marketplace to respond. 

Minimum performance thresholds have been increased in some cases, and decreased in others. For example a prerequisite of 20% savings was established for Water Efficiency, and points are earned at 30% and 40% savings.  Version 1.0 of LEED NC had no prerequisite and rewarded one point for 20% and two points for 30%. Most projects can easily achieve 20% water use reduction based on available low-flow fixtures, or by simply meeting local building code requirements in many cases.

In other categories, LEED Canada 2009 decreases performance thresholds.  The requirements for MRc6 Rapidly Renewable Materials were reduced from 5% to 2.5% is in response to the low number of projects able to achieve a demonstrated performance of 5% or greater.  Reducing the threshold should encourage projects to pursue this credit, recognize them for it and thus create more demand in the market place for compliant products.

The most significant overall change to the rating system is almost certainly the reallocation of credit weighting. To better account for their environmental benefit, credits have been evaluated using a life cycle methodology and re-weighted accordingly.  This has increased the available point total, and further shifted the credit count in favour of Energy & Atmosphere, acknowledging the significant contribution of building energy consumption to climate change.  The rating system now includes a total of 110 points and one additional prerequisite, as compared to Version 1.0’s 70 total points. Thirty-five of those 110 points (or 32%) are within Energy and Atmosphere, where 17 out of 70 (or 24%) were available in Version 1.0.  It is important to note too, that process energy must now be accounted for in the predictive energy model where it was excluded in Version 1.0.

 More Flexibility

More flexibility has also been incorporated into LEED Canada 2009   Additional compliance paths have been added to some credits where alternative approaches clearly meet the intent of the credit. For example, an additional option to achieve Community Connectivity (SSc2) without meeting the density requirement for the credit is allowed for a subset of points, and a new pathway for meeting the SSc5.2 (Maximize Open Space) is included for sites with local zoning but no open space requirements.

In addition, clarification has been added to many ambiguous compliance requirements based largely on the database of credit interpretation requests and obvious vague statements.  For instance Commissioning Authority experience and independency requirements are clarified, and clear explanations are included on when a VOC budget can be used.

Finally, in order to recognize environmental issues of particular local significance, Regional Priority credits have been introduced.  Up to three points can be earned by projects that demonstrate that an existing credit has special regional significance. 

 Streamlining

Applicants can also look forward to a streamlined certification process as the Canada Green Building Council moves to a two-stage review instead of three as required in Version 1.0, which should greatly reduce the length of time required to achieve certification once project documentation is submitted.

The future of LEED will see many more iterations, and new rating systems such as ND (Neighborhood Development) and Homes will be added to the toolkit to provide a more comprehensive approach to greening the built environment. The value of LEED has been demonstrated; it is the green building rating system with the most traction in the North American market place (and increasingly beyond), and the industry is now recognizing that LEED is not just about points and recognition – it creates accountability in practice. 

Where LEED Canada has yet to go with new construction, is ongoing performance monitoring to maintain certification.  The next logical step is to incorporate post-occupancy assessments to verify predicted building performance. A verification requirement would bridge the gap between design and performance, take the program to the peak of accountability, and provide invaluable learning opportunities to inform future work.  LEED Canada 2012 may assume this important component, but until then the program will continue to drive incremental, rather than transformational design improvements.

 Rebecca Holt, M. Urb., LEED AP BD+C  is a Sustainability Specialist with Stantec in Vancouver, and Klaas Rodenburg, MA, CET, LEED AP BD+C  is a Sustainable Design Coordinator with Stantec in Edmonton.


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