EPA Region 8 Headquarters: Denver, CO
This building harnesses the natural resources of Denver's climate. The nine-story atrium provides daylight to the lobby and internal offices, while parabolic sails prevent solar heat gain and glare. The building's 20,000 ft2 vegetated roof is used as a stormwater management system. A daytime cleaning program reduced the building's energy costs in 2007 by 28%, saving nearly $250,000.