Mission: HousingSan Francisco, CA 94110
Design Achievement - Mission: Housing showcases mass timber as a tool for alternative development, providing affordable housing that does not prompt demolition to existing buildings. The El Capitan Theater & Hotel, built in Mexican Baroque Churrigueresque style, is an exquisite historic resource at risk of neglect. DLR Group, collaborated with structural engineering firm DCI Engineers on the design of Mission: Housing, a modular timber tower atop a landmark building in San Francisco’s Mission District for “Plan B: The City Above the City,” an international wood building competition hosted by Metsa Wood. DLR Group’s design concept re-adapts the original building with strategic intrusions to the existing structure and embraces the affordability of its current use while reconnecting the site to the surrounding community. The building form directly responds to its context through tapering and shearing; it is sensitive to the existing life of the street while increasing density. The skin system references Churrigueresque patterning on the existing base yet expands and shifts across its height to reveal lush gardens and an expanding array of delicate canopies.
Proposed system assemblage for Mission: Housing. Image © DLR Group.
Scope Summary - The scope of work for this design competition project encompassed 280 housing units on 26 new floors atop an existing 3-story building, totaling 180,000 SF. Key amenities include a public green space, and a community space. The design applies an innovative composite floor system comprised of concrete topping with steel shear plates embedded into laminated veneer lumber floor panels, allowing for longer spans. Sandwiched joists in this floor design permits the bottom panel to be removed and replaced in the event of fire damage, enabling the building to be reoccupied quickly after a fire event. Additionally, heavy timber columns employ steel plate connections that minimize shrinkage between floors. Flexibility is enhanced by the lateral force resistance of post-tensioned laminated veneer lumber rocking shear walls, which can be recalibrated as necessary to maintain optimal strength or resolve shifts in structure after an earthquake. The high compressive capacity of these wall panels makes them incredibly resilient, handling large seismic forces while exhibiting minimal damage. Since the construction process uses a prefabricated panel kit-of-parts approach, this solution is highly efficient and flexible for future growth. DLR Group provided architecture design services.