The addition will add approximately 100,000 square feet of gallery and public space to the existing 225,000 square feet building and approximately 60,000 square feet of support space including larger and more advanced conservation facilities and an expanded library. SFMOMA also plans to relocate administrative support space into the new facility, consolidating all staff offices in one on-site location. In addition, the expansion might also include a new entry on Minna Street along the museum’s northern facade to improve access for school groups and for visitors to public programs in the museum’s Phyllis Wattis Theater.

Led by architects Craig Dykers and Kjetil Thorsen, Snøhetta beat four finalists competing for the project. Snøhetta was chosen for its earlier work on National Opera and Ballet in Oslo, Norway, which features stunning spaces, sophisticated use of materials, and spectacular lighting.

The announcement by SFMOMA follows a comprehensive international search and two-year planning process to address the growth of its collections and audience demand for programming since the museum moved to its current building in 1995. Snøhetta will partner with a local architectural firm to execute the expansion and will join SFMOMA’s project team after the contract is completed.

Initial design concepts for the project will be unveiled in April 2011.

Construction will start on site in 2013, with the gallery due to open in 2016. The total project budget is $480 million, which includes $250 million for the expansion and $230 million for SFMOMA’s endowment to ensure the museum’s long-term success.