Developers Turn Former Office Buildings Into High-End Apartments - The Wall Street Journal

Historically, office space has commanded substantially higher rent than residential space. But that is starting to change, especially for older buildings that have lots of architectural charm—often located in urban downtowns—but are no longer desirable as top-notch office space.

At the end of 2013, the U.S. apartment vacancy rate stood at 4.1%—the lowest since the end of the dot-com boom in the early 2000s, and below its 5.7% average rate since 1980, according to an analysis of 50 top markets by property-data firm Reis Inc. Meanwhile, the office vacancy rate was 16.7%—only a nudge down from the 17.6% post-economic crisis high reached in 2010 and well above its average of 14.9% since 1980.