Green buildings are having a positive effect on saving energy, water, land, materials, and indoor environments, but the progress is insufficient to adequately curb global climate change, according to the “Green Building Impact Report,” coauthored by Rob Watson, executive editor of GreenerBuildings.com, and Elizabeth Balkan.
The report is the first integrated assessment of LEED’s impact on energy, water, land, materials, and indoor environments, and the first to assess how much green buildings have improved the environment.
According to the report, the carbon footprint of commercial buildings in the U.S. will need to decline each year by about 1.6% to reach a reduction goal of 80% by 2050. LEED buildings are already ahead of this goal, according to the report, but the entire building sector needs to hit these marks to have a real impact on global warming.
Among the report’s findings:
• Land. Nearly 400 million vehicle miles traveled have been avoided by occupants of LEED buildings, owing to efficient locations and transportation options. By 2020, LEED buildings are expected to eliminate more than four billion vehicle miles.
• Water. Expected water savings from LEED commercial buildings will grow to more than 7% of all nonresidential water use by 2020.
• Energy. LEED buildings consume about 25% less energy than comparable non-LEED buildings. By 2020, energy savings should amount to more than 1.3 millions tons of carbon equivalent each year, which equals the elimination of about 78 million tons of carbon dioxide emissions.
• Materials and resources. LEED-certified projects account for $10 billion in green material purchases, and should rise to $100 billion by 2020.
• Indoor environments. Companies with employees working in LEED buildings realized annual productivity gains exceeding $170 million, owing to improved indoor environmental quality. By 2020, this figure could reach nearly $2 billion in annual productivity gains.
The report can be accessed at: www.greenerbuildings.com/gbir08