The Smithsonian's Hirshhorn Museum and Sculpture Garden is considering a temporary, bubble-like addition to cover the courtyard at the center of its round building.
The concept of a 145-foot inflatable meeting hall was first reported Tuesday. It would look like a balloon expanding through the roof of one of the monumental buildings along the National Mall.
Museum director Richard Koshalek wants to create a place to discuss contemporary cultural issues. He has said the Hirshhorn should be an "ideas factory." Initial plans call for up to 1,000 seats in the structure.
The museum estimates it will cost about $5 million.
As a temporary structure, it would not require the approval of the National Capital Planning Commission.
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