Friday, November 28, 2008
Are Green Buildings Really Having an Impact?
So much new information is announced during the U.S. Green Building Council's annual conference that it is impossible to sort through all of it in real time, but now that I have had time to unpack from my trip to Boston, I thought I would try to illuminate some of the most important, one blog post at a time over the next few weeks.
Let's start with a report released by Rob Watson, who led the development and implementation of the LEED Green Building Rating system from 1994 to 2005. The Green Building Impact Report (GBIR) is the first integrated assessment of the land, water, energy, material and indoor environmental impacts of the LEED for New Construction (LEED NC), Core & Shell (LEED CS) and Existing Building (LEED EB) standards. Watson's team says that LEED Certified projects represent more than 6% of new commercial construction, but there has been an astronomical ramp-up in the past year of new project registrations, with new construction sector penetrations approaching a whopping 40%. On average, it takes approximately two years from Registration to Certification, with an attrition rate of 25% to 30%.
Among their other findings:
Non-residential construction, the focus of the report, represents about 40% of the environmental burden of buildings.
Land Use. Between efficient location and the myriad of alternative transportation options supported by LEED, nearly 400 million vehicle miles traveled have been avoided by the occupants of LEED buildings. This grows to more than 4 billion vehicle miles by 2020.
Water. Water savings from LEED commercial buildings to grow to more than 7% of all non-residential water use by 2020. The equivalent of 2008 LEED water savings would fill enough 32-ounce bottles to circle the Earth 300 times.
Energy. LEED saves energy on many different levels, including energy related to operations, commuting, water treatment and the lower energy embodied within materials. In operational energy terms, LEED buildings consume approximately 25% less on average than comparable commercial buildings. By 2020, these energy savings amount to more than 1.3 million tons of coal equivalent each year, representing approximately 78 million tons of carbon dioxide (CO2) avoided emissions.
Materials and Resources. LEED has helped spur an entire industry in green building materials. Certified projects to date have specified a total of more than $10 billion of green materials, which could grow to a cumulative amount exceeding $100 billion by 2020.
Indoor Environmental Quality. Indoor environmental quality is the most important contributor to the productivity attributes of LEED. They calculated that companies with employees working in LEED buildings realized annual productivity gains exceeding $170 million resulting from improved indoor environmental quality, a number that will grow to nearly $2 billion of annual productivity improvements by 2020.
Posted by William M. Brown, AIA, LEED AP