Tahanan Supportive Housing

This modular building prototypes a financing and construction approach intended to speed production of permanent supportive housing in San Francisco. Completed within schedule and cost goals, Tahanan was realized 30% faster than similar local projects. The six-story community—five levels of modular construction over a concrete podium—offers furnished studios for formerly unhoused residents. Fabricated and finished off-site, each module includes two complete units plus a segment of connecting corridor. The compact homes top a community-focused ground floor with social services and a flexible common room linked with a vibrant courtyard. High ceilings and extensive glazing fill the space with light while balancing security and transparency. The sawtooth facade orients windows toward downtown views, and the rainscreen of weathering steel and natural aluminum is perforated for integrated venting. The site falls within a Filipino Heritage District, intended to preserve diversity with attention to Filipino American culture. Local organization SOMA Pilipinas shared references and imagery that informed design elements throughout, including the use of the traditional woven mats to pattern textured concrete and a rice terrace graphic in the metal stair tower. Tahanan is a Tagalog word evoking “coming home” and represents a place for people to return or rest.

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In terms of an affordable project, it’s quite refined, especially on the interiors. | The one-bay window strategy makes each unit quite nice. | The shared spaces are inviting. | The materials are proud.

//framework for design excellence measures
Measure 1: Design for Integration
Tahanan provides desperately needed housing that is both efficiently constructed, yet distinct to the neighborhood, dignified and resilient. Design integration was necessary to meet three intersecting imperatives of the project: serving formerly unhoused residents; serving the community; and fast, affordable delivery.
A prime example of this integration is the panelized metal rain-screen system used to clad the building, designed in conjunction with BOK Modern, a San Francisco-based fabricator. The cladding—alternating weathering steel and natural aluminum—simplifies the exterior wall assembly while adding depth and character. Perforated patterns in the metal follow a mega-graphic inspired by Philippine rice paddies and cloak the full height of a feature stair as an outward, civic gesture, while also employed to conceal penetrations, eliminating the need for exterior vent hoods.
Measure 2: Design for Equitable Communities
Principles of trauma-informed design shaped details of the building, from color and material selection, to thoughtful pockets for refuge or gathering, to a sense of security in the layout of the courtyard, lobby, services offices, and corridors. The secure bike shed is accessible, visible and inviting; building-wide internet is standard; and the project is permanently staffed with case workers for support services, such as light health care, counseling, and job training.
Measure 3: Design for Ecosystems
Previously a completely paved parking lot, the site now sends naturally treated stormwater slowly to the Bay. The landscape design emphasizes native and drought tolerant plants and added street trees, with new landscaping visible from the street through the common areas and lobby. The sheltered courtyard, lined with art, plantings, and seating, draws residents outside to experience fresh air and sunshine. 
Measure 4: Design for Water
The project employed typical water-saving fixtures and irrigation design, in addition to some aggressive efficiency measures like metered faucets. 
Measure 5: Design for Economy
To meet the project’s ambitious delivery and budget targets, the modular construction type was exploited for maximum efficiency, limiting variability of features where it counts for the production line and transportation process. The project embraces the beauty of exposed systems, raw materials, imperfection and change, with low-maintenance surfaces set off by art and evocative textures. Common program is designed with flexibility in mind, with a community room designed intentionally for multitude of uses (community gatherings, presentations, meetings, training sessions, lounge).
Measure 6: Design for Energy
Permitted prior to San Francisco’s ban on new natural gas, an analysis found that gas-fueled central hot water combined with maximum roof-mounted solar PV was the best fuel system combination when optimizing for cost. This runs counter to carbon reduction and was a wake-up call for equitable decarbonization in dense urban contexts. The team leveraged high-efficiency packaged heat pumps, appliances, and lighting, as well as utilizing integrated window shading. A series of in-depth trainings for building operators reinforced efficient operation of central hot water, lighting controls, and a central monitoring system for submetered energy and water use.
Measure 7: Design for Well-Being
Place-based and trauma-informed design shaped details of the building, creating a safe and uplifting experience of coming home, starting at the street and ending with views oriented to draw attention to the San Francisco skyline. GreenPoint standards for non-toxic finishes were prioritized for the higher-risk resident population. Air conditioning was also provided—which is atypical for San Francisco—as a resilience and health measure, along with MERV 13 supply ventilation, to protect residents from the worst effects of extreme weather events. 
Measure 8: Design for Resources
The project successfully coordinated and achieved 25% cement replacement in all concrete, in addition to employing innovative, low-waste concrete formwork. The lowest impact materials are the ones not used, and so exposed ceilings and ductwork are among the strategies to limit material use and cost on the project. The prefabricated, panelized single-material cladding system eliminated complex assembly (furring, fasteners), while also serving as a bold architectural gesture. There is further resource efficiency in factory production, most notably bulk procurement, less intensive and complex procurement and transport of materials to the site. 
Measure 9: Design for Change
This project provides durable, healthy, stable, and sustainable long-term supportive housing for 200+ people that were formerly unhoused in San Francisco, contributing to the overall safety and resilience of the city. 
Measure 10: Design for Discovery
The design and development team utilized the design process to learn about the replicability of the financing and construction model used to deliver the project on budget and schedule. We have collected detailed information about the delivery process to study resource use and material efficiency in modular construction in more detail. Ongoing relationships between architect and client ensure that surprises and failures of the spaces in use for a diverse, sometimes struggling yet resilient resident population are fed back into the design of future permanently supportive housing projects.