By Adam Cohen
In the United States when we discuss “green building” the conversation inevitably turns to the US Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) system. The LEED system currently ‘leads’ in the certification of large commercial projects with over 2 billion square feet of space as of mid-2012! I find two recurrent misperceptions of high performance building; first that “one certification is as good as the next”, and second that “all green buildings use less energy.”
In reality, the first misperception could not be farther from the truth. There are many certifications available to an owner and each one has both pros and cons. I show my clients that by employing a well thought out holistic strategy towards high performance building we can reveal the synergies within the competing systems and achieve certification in several systems, if wanted.
The second misperception that “all green buildings use less energy” is also not true. Just because a building wears a “green” label does not mean lower energy use. In fact, some green certifications have been shown to deliver very little in terms of real world energy savings, with some “green” projects actually using more energy!
Passivhaus (aka “Passive House”) has over two decades of data that consistently show lower energy use with very accurate energy use projections. When Passivhaus and LEED are combined on a project, tremendous synergies occur. As an example, the Center for Energy Efficient Design (CEED) designed and built in 2010, received both Passivhaus and LEED certification. In the LEED system the levels of certification are determined on a point system as follows:
- Certified 40–49 points
- Silver 50–59 points
- Gold 60–79 points
- Platinum 80 points and above
Here is a quote from Gail Hampsmire, P.E., LEED AP BD+C, Technical Director, HVAC/Energy Team at the Green Building Certification Institute (GBCI)* regarding the Center for Energy Efficient Design:
“For this project, an impressive 33 points, representing 41% of the total points required for LEED Platinum have been rewarded for the energy efficiency and indoor air quality benefits achieved using the Passive Haus Certification Strategy”.
This quote demonstrates the strength of Passivhaus Certification when applied to a LEED project. Not only will Passivhaus help the project gain in certification level, the building owner is assured of durable, long-term reduction of both energy and maintenance costs.
So Passivhaus vs. LEED is a false dichotomy. In reality Passivhaus + LEED are in perfect harmony!