Energy usage...

ArchitectureWeek: "Residential and commercial buildings are conventionally thought of as consuming 38 percent of energy in the United States. But when he adds in building-related industrial consumption - such as HVAC systems and building materials in factories - he calculates that architecture's share is actually closer to half the country's total energy consumption. Similarly, architecture is responsible for 46 percent of U.S. carbon dioxide (CO2) emissions. "