Of the 30 largest commercial real estate markets in the U.S., Chicago has the most LEED- or Energy Star-certified office buildings, at 66% of total inventory, according to the 2017 National Green Building Adoption Index, published by CBRE and Maastricht University.
The report found that Chicago boosted its percentage of green office space by 6.5% since last year, ousting San Francisco, which came in at 62%, from the top spot. Atlanta (55.1%), Houston (53.2%) and Minneapolis/St. Paul (50.9%) rounded out the list of the five cities with the most certified green office space.
Researchers determined that throughout all 30 markets, LEED and Energy Star office space is at an average of 38%. They said going green is no longer a special offering but a feature that prospective tenants have come to expect.
The greening of Chicago's office buildings has gotten a helping hand from city officials, who have offered up incentives for developers to install features like green roofs, , Bloomberg reported. The city also provides a streamlined permitting process for buildings that have incorporated certifications like LEED and Energy Star into their plans.
The city has also aimed for increased sustainability for its own buildings. In April, Chicago Mayor Rahm Emanuel announced that more than 900 city-owned buildings will shift to all renewable energy by 2025, making it the largest municipality in the country to make such a commitment.
A Harvard T.H. Chan School of Public Health study published late last year found that those who worked in certified green buildings were able to think and plan at a rate 25% higher than workers in non-certified buildings and had 6% better sleep quality. Researchers chalked up the difference to the improved lighting, thermal control and ventilation in green buildings, as well as to the "delight factor" of working in such an environment.
A 2016 World Green Building Council report also linked improved employee productivity to green office features. The WGBC said employees can account for as much as 90% of a company's operating costs, so even a slight increase in their productivity can result in a meaningful boost to the bottom line.