Photos: Sizing up Chicago's green high rises

When it opened in 2005, 111 South Wacker became Chicago's first LEED-certified tower. The 51-story, 121,000-square-metre office building features energy-efficient lighting, paints and carpeting with minimal toxic ingredients, as well as recycled, locally sourced materials.

Viracon glass helps to insulate heat and noise. The builders reused most of the foundation from the building previously located on the site. The sloping, spiral ceiling of the lobby is shaped by the parking garage above it.

Credit: Gregory Wenzel