The former Colt firearm factory in Hartford, Connecticut, has been transformed into a mixed-use facility including retail space and offices. (Shutterstock)

Over the last 100 years, more than 4,200 buildings have been converted into office space through adaptive use across the United States, according to a report from data provider Yardi’s Commercial Search. Primarily, those conversions were from industrial space (61 percent), followed by retail (19 percent) and residential (5 percent).

Here are some key takeaways from the study:

  • While 90 percent of conversions happened in the past 40 years, one-fifth occurred during the 1980s—the period when office adaptive use in urban areas surged—and 53 percent since 2000.
  • California is the first state in the country in terms of adaptive use of offices, with 595 structures converted to office space over the past century. New York comes in second with 510 buildings.
  • The top three cities in this respect are New York City, Los Angeles, and Boston, with 270, 184, and 161 converted buildings, respectively, representing a combined 70 million square feet (6,503,200 square meters).

Yardi: 4,283 U.S. Office Buildings Created Through Adaptive Reuse in Last 100 Years