San Francisco Museum of Modern Art Expansion

Team

Architect

Snøhetta, w/Esherick Homsey Dodge & Davis

Contractor

Webcor

Stats

PROJECT TYPE

Museum

COMPLETION

2016

PROJECT SIZE

225,000 ft²

MKA ROLE

Structural Engineer

San Francisco, CA
San Francisco Museum of Modern Art Expansion

This 10-story expansion’s transformative design seamlessly connects to the existing and iconic art museum designed by Mario Botta to double the museum’s current gallery space and provide a unique experience for visitors. A large, glass-walled gallery and an outdoor sculpture terrace featuring San Francisco’s most prominent living wall of native plants comprise some of the new and expansive gathering spaces.

A daylight aerial view of the San Francisco Museum of Modern Art Expansion with surrounding buildings

“Egg Crate” Solution Saves Millions

When the San Francisco Museum of Modern Art embarked on a plan to double the size of its museum, the project team faced a unique challenge. The site’s existing mat foundation—just four feet, six inches thick—could not support the proposed 200-foot-tall addition. Demolishing the mat foundation would compromise the existing building, and drilling large piles through the mat foundation was too expensive.

MKA collaborated with the architect, geotechnical engineer, and contractor to create an innovative solution nicknamed the “egg crate.” This bolstered foundation system incorporated a series of full-story-deep concrete stiffening walls with embedded steel columns, creating a stiffened box—much like an egg crate—to spread the building’s loads out and enhance the capacity of the existing mat foundation.

Reusing and repurposing the existing mat foundation reduced the building’s new materials and embodied carbon, saved the owner more than $1 million in foundation costs, and shortened the construction timeline by almost three months.