British architect David Chipperfield was contracted to design the expansion which will include 82,000 square feet of new galleries and public space.
"Our practical goals for the expansion are to create incremental gallery space for our permanent collection, to enhance public infrastructure that's in short supply in our historical building and to enhance some infrastructural shortcomings that affect the operation of the institution," said Brent Benjamin, the museum director.
The expansion will be the largest capitol campaign for a cultural institution in St. Louis history; the museum has already raised $100 million towards its goal.
The expansion will create an additional entrance to the left of the current entryway and wrap around to the back of the original Cass-Gilbert building.
"This is not an exercise of humiliation of the original building but on the opposite, its one of fortifying the status of the rather wonderful Cass-Gilbert building with its infrastructural issues," says David Chipperfield.
The project will add over 82,000 square feet of new gallery space as well as a 300-spot below ground parking garage.
Chipperfield is a modernist architect, having completed a number of renowed projects across the globe and closer to home, including the Figge Art Museum in Davenport, Iowa, as well as the Central Public Library in Des Moines.
He's also working on an expansion of the Anchorage Museum in Alaska.
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