While the layout of the southern California metropolis has been synonymous with ''sprawl,'' recent regulations have made Los Angeles ripe for green building.
In 2009, the city unveiled the Green Building Retrofit Ordinance, a law requiring city-owned buildings built before 1978 or larger than 7,500 square feet (696.8 square meters) to be refurbished with environmentally friendly materials [source: Database for State Incentives for Renewables & Efficiency]. In 2010, the state government adopted a green building code requiring new homes and commercial and public buildings to cut water consumption by 20 percent over the previous code. Builders also had to begin using low-polluting construction materials and discarding half of construction waste in areas other than landfills [source: Roosevelt].
According to a 2010 Environmental Protection Agency survey, Los Angeles was home to 510 Energy Star-certified buildings for a total of 106.1 million square feet (9,857,013 square meters) -- more than any other city in the country [source: Catacchio].