The San Francisco Museum of Modern Art has shortlisted four firms to design a new expansion for the museum: David Adjaye, Diller Scofidio + Renfro, Snøhetta, and Foster + Partners. The first three names rooftop sculpture garden.

The expansion will be located around the corner at 670 Howard Street and an adjacent firehouse for which the museum is building a replacement on nearby Folsom Street. The new building is expected to add about 100,000 square feet of gallery and public space. Much of the administrative and conservation spaces will also be consolidated into the new building, covering about 60,000 square feet, freeing up additional gallery space in the Botta building as a result.

Museum spokesperson Libby Garrison cautioned that these are more general guidelines than specific numbers, as the idea is to give the designers leeway to create the best fit between new and old. Still, it appears that gallery space could expand to three or four times its current capacity. Another open question is how to connect the two buildings, perhaps with a bridge or tunnel, as they are separated by an alley that must remain open. Again, the museum is leaving this decision up to the designers.

“At this point, we weren’t seeking a design, we were seeking a designer,” Benezra said. “Many things will change about the design from this initial foray into a general concept, over the course of the next year. Maximum flexibility will be key to the gallery design. As a contemporary art museum it is incumbent upon us to stay responsive to new art as it is made.”

Benezra said the four firms were selected from a larger group—comprised of whom he would not say, though he insisted some local firms were considered “very seriously." This initial group was asked to submit abstract proposals, without being given a formal program from the museum, with the four best entries landing the commission.

Benezra said that while the parameters of the museum will continue to change, his chief concern is the feel of the new space.“Light in museums is everything, because it so determines the presentation of the art,” he said. “Whenever I’m in a museum, I always want to see how the architect got the light into the gallery. It’s a very particular design problem.”