Chicago is the top market in the U.S. for sustainability, with 66% of its office building footprint qualified as green, according to the fourth annual Green Building Adoption Index study by CBRE and Maastricht University.

The study, which centered on the top 30 U.S. office markets, determined that institutional investors continue to seek green building certifications. Energy Star certifications account for 10.3% of all buildings surveyed and 4.7% of those buildings attained LEED certifications. In the top 10 markets, the drive toward green and sustainable is mostly driven by local governments: Nine of the top 10 markets have implemented benchmarking ordinances for sustainability, including Chicago.

Tenant demand is another driver. Twelve of the top 25 Chicago-area lease transactions in 2016 were in LEED-certified buildings; those 12 deals totaled 3M SF. The deliveries of 150 North Riverside and River Point increased Chicago's green office building stock by 6.5%, enough to claim the top spot from San Francisco.