Buildings do not exist in a vacuum: they shape the world around them by their very presence. A green building can further contribute to the local environment in three main ways: sensible handling of water, reduction of the "heat island effect" found in urban metro areas, and proximity to amenities and public transport so occupants have options other than driving. The logical extension of this approach is called "New Urbanism" in which communities are designed to minimize sprawl and the need to drive. While most "New Urbanist" development is not oriented around green building specifically, this pattern of building still greatly reduces net environmental impacts.

In Chicago, our main water concern is how "stormwater" is handled. For example, a paved parking lot forces all the rainfall (which may contain motor oil, gasoline and other contaminants) directly into drains to the lake. A "permeable" parking lot would allow the water through into the ground where it would be absorbed slowly into the earth, helping reduce flooding and lake pollution.

Similarly, in summer, roadways and buildings with dark roofs soak up heat which is radiated into the environment. This effect produces "heat islands" where cities and surrounding areas are several degrees hotter than rural areas. A green roof or other mitigation efforts can reduce the net effect. These are minor factors but certainly worth taking into consideration when building green. Chicago's building codes now require all new roofs to be light in color to help reflect heat.

Additional Resources
Congress for the New Urbanism
Smart Growth and Sustainable Development
Chicago's Heat Island Effect
More on Heat Islands