The design, construction, and maintenance of buildings create a tremendous impact on our environment and our natural resources. There are more than 850 million residential buildings and nearly 65 million commercial buildings in the world today. These buildings together use one-third of all the energy consumed globally, and two-thirds of all electricity. By the year 2015, another 120 million buildings are expected to be constructed. The challenge will be to build them smart, so they use a minimum of nonrenewable energy, produce a minimum of pollution, and cost a minimum of energy dollars, while increasing the comfort, health, and safety of the people who live and work in them. Furthermore, buildings are a major source of the pollution that causes urban air quality problems and the pollutants that contribute to climate change. They account for 49 percent of sulfur dioxide emissions, 25 percent of nitrous oxide emissions, and 10 percent of particulate emissions, all of which damage urban air quality. Buildings produce 35 percent of the global carbon dioxide emissions, the chief pollutant blamed for climate change. Traditional building practices often overlook the interrelationships between a building, its components, its surroundings and its occupants. "Typical" buildings consume more of our resources than necessary, negatively impact the environment and generate a large amount of waste. According to industry statistics, a standard North American wood-framed home consumes over one acre of forest and the waste created during construction averages from 3 to 7 tons. Often, these buildings are costly to operate in terms of energy and water consumption and they can result in poor indoor air quality, which can lead to a multitude of health problems. There are many opportunities to make buildings cleaner. As just one example, if only 10 percent of homes in North America used solar water-heating systems, we would avoid 10.5 million metric tons of carbon emissions each year. Green building practices offer an opportunity to create environmentally sound and resource-efficient buildings by using an integrated approach to design. Green buildings promote resource conservation, including energy efficiency, renewable energy and water conservation features; consider environmental impacts and waste minimization; create a healthy and comfortable environment; reduce operation and maintenance costs; and address issues such as historical preservation, access to public transportation and other community infrastructure systems. The entire life cycle of the building and its components are considered, as well as the economic and environmental impact and performance. More and more designers, builders, and building owners are becoming interested and involved in green building. Global, national and local programs encouraging green building are growing and reporting successes, while thousands of demonstration projects and private buildings across the globe provide tangible examples of what green building can accomplish in terms of comfort, aesthetics, and energy and resource efficiency. |