Theophilus van Kannel was born in Pennsylvania in 1841. Though his past is mysterious, it is believed that van Kannel invented the revolutionary door in order to avoid having to hold doors for women. According to the podcast 99% Invisible, "There was nothing he despised more than trying to walk in or out of a building, and locking horns with other men in a game of 'oh you first, I insist.'"
He patented his "storm-door structure" in 1888, which included weather stripping to prevent energy loss. The first revolving door was installed at a Times Square restaurant called Rectors in 1889. This invention solved numerous problems that traditional doors couldn't answer. They help regulate temperature and air pressure, thereby saving up to 30 percent of energy costs. An MIT study also found that they exchange eight times less air than traditional doors.