Buildings impact our environment and our bodies in many ways, and many are not visible to the naked eye. By implementing green building techniques a buildings potential performance both economical and environmental can be maximized.

Continuing research is proving all of these benefits and costs of green building, and of how to achieve the greatest benefits at the lowest costs. Development of new properties takes a significant toll our natural resources, including:

• According to 2002 surveys, 107.3 million acres of the 1.983 billion acres of total land in the U.S. is developed, which represents an increase of 24 percent in developed land over the past 10 years.
• In terms of energy, buildings accounted for 39.4 percent of total U.S. energy consumption and 67.9 percent of total U.S. electricity consumption in 2002.
• Home owners and businesses use are responsible for 12.2 percent of the total water used in the U.S. Buildings both residential and commercial and the transportation industry are responsible for replacing natural surfaces with weather resistant materials, creating runoff that washes pollutants and sediments into surface waters. Urban runoff constitutes a major threat to water resources, as it has been identified as the fourth leading source harming rivers, third in lakes, and second on adjoining bodies of water.

The energy used to heat and power our buildings uses enormous amounts of energy, mainly from the burning of fossil fuels such as oil, natural gas and coal - which generate significant amounts of carbon dioxide (CO2), the most widespread greenhouse gas. Buildings in the U.S. contribute 38.1 percent of the nation's total carbon dioxide emissions.

Reducing energy use and therefore greenhouse gas emissions produced by buildings is essential to help slow changes in the global climate. Buildings may be associated with the release of greenhouse gases in other ways, for example, construction and demolition debris that breaks down in landfills may produce methane. The removal and manufacturing of building materials may also cause greenhouse gas emissions.