The US Department of Energy Building Codes Program created ‘Residential Requirements of 2009 International Energy Conservation Code’. The code is applicable to all new home construction. Before these criteria were developed, there were no requirements for lighting or home appliances. Below are the highlights.
-50% of permanently installed lighting fixtures have to be high-efficacy lamps (has to take CFL’s or LED’s only, has to be pin-based not a medium/standard base) All fixtures rated Energy Star will meet these requirements.
-All recessed cans must have IC (insulated ceiling) rated housings with a gasket or airseal.
These criteria are required in most states. You can find out more information at www.energycodes.gov