Renowned architect Renzo Piano unveiled his preliminary designs for the 90,000-square-foot new building, which will be directly in front of the existing museum, similar to its height and scale and constructed of the same materials: travertine marble, glass and concrete.
The project will be complete in 2012 and includes a larger auditorium and new underground parking garage.
The Kimbell, designed by Louis Kahn, was hailed as a landmark of modern architecture when it opened in 1972.
But the museum has lacked the gallery space to display a major temporary exhibition and its entire permanent 350-piece collection, which ranges in period from antiquity to the 20th Century, said Malcolm Warner, the Kimbell's acting director.
Piano has built three museums in Texas: the Nasher Sculpture Center in Dallas, and the Menil Collection and the Cy Twombly Gallery in Houston.