01 THE THICKENED WALL
02
URBANISM FROM WITHIN
THE HORIZONTAL CORE
03 THE PRIVATE PARKLET
04 THE PUBLIC INTERFACE
05 THE LIFTED GARDEN
06 THE DOUBLE DECKER
07 THE MICRO-VERTICAL
08 POROSITY FROM ABOVE
09 THE COMMON LIGHT
10 THE SIDE COURT
This exhibition catalogue explores the typology of the secondary unit in San Francisco and its interaction with the larger systems of a city to test how a diffused form of individual interiors creates new connections, power structures, forms of sharing, cross-pollinization of public and private realms, and formal architectural mutations. How can the interior reformat urbanism from within to help solve the city’s housing shortage?
00 01 URBANISM FROM WITHIN
Neeraj Bhatia and Christopher Roach
The interior and urbanism are often positioned at opposite poles of spatial praxis, with architecture acting as a mediator - separating the inside from outside and scaling the individual to the collective. Increasingly, we are witnessing the aggressive adjacency between the interior and the urban environment, as a mechanism to mitigate topdown planning with bottom-up power structures. This scalar shift is witnessed not only in the commonly discussed “interior urbanism” of large shopping malls or continuous conditioned spaces, but also where micro-changes to a series of diffused interiors accumulate to have a collective effect on the urban environment. By examining the interface between the interior and urbanism, it allows one to speculate on how the city can be reformatted from within. In recent years, San Francisco has become emblematic of the difficulties of managing rapid urban growth in a culture entrenched in NIMBYism. A severe deficit of new housing, coupled with an influx of jobs primarily in the tech sector, has caused rents and housing prices to soar to the highest in the country. Silicon Valley’s economic engine has rapidly created a new wealthy class in a more urban-oriented generation, and this has fueled the
fire of a geographically and politically constrained housing pressurecooker. This is most overtly reflected in widespread gentrification and socio-economic homogenization as the lower and middle class continue to be priced and pushed out to the city’s periphery. Despite the almost hysterical declarations of a housing crisis, as well as the unparalleled political will of an almost monolithic progressive populace, San Francisco is still consistently hamstrung by its own romantic image of the city as a low-rise fabric of Victorian Houses nested on picturesque hills by the Bay. Yet, even if there is widespread agreement that the city must densify and provide more housing if it is to survive the 21st century, this image has remained remarkably durable - an idée fixe justified by a tourism industry that is robust and growing.1 San Francisco’s Mayor Ed Lee has plans for the construction of 30,000 housing units by 2020, which, while ambitious, falls far short of the City’s Chief Economist’s requirement for at least 100,000 market-rates units to noticeably impact prices.2 Conventional models of housing development, whether marketdriven or government-sponsored, move too slowly and require such large amounts of land and capital that they will never meet even this modest goal. Accordingly, the Mayor has challenged architects, builders, policymakers, and planners to develop innovative tactical models for providing new housing within rapid timeframe.
DIFFUSION AS A MODEL FOR DENSITY While the high cost of housing in San Francisco may be superficially linked to an emerging wealthy demographic, the core of this issue lies in the lack of supply within the city. This is primarily a result of well-intended housing policies that have limited the amount of development and density in an effort to preserve the urban fabric and it’s associated street-life. One of the mechanisms of controlling rapid inflation was through a rent control policy enacted in 1979. While originally established to protect residents, most economists now believe that such policies create shortages in housing, ironically resulting in increased prices.3 This has re-parsed the city into “haves” and “have-nots” - those that own or have rent-controlled housing, and those that have recently moved or otherwise been thrown into an inflated housing market. From the economist’s point of view, the lack of land area in a city constrained by geography has been compounded by artificial price controls and a regulatory environment that equally hinder the production of new housing, resulting in a housing market unable to maintain supply for affordable units. Nonetheless, one of the critical mechanisms to escape the housing crisis and its associated ramifications is to increase the availability of affordable units through densifying the city.
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
Density has primarily been understood within contemporary urbanism through the development of new collective housing clustered around a focal point or street. In the context of San Francisco’s welldefined urban fabric, this notion of density is typically envisioned as high-rise condominium development. Accordingly, the tower as a type has created an architectural lightning rod that encapsulates the fears of high-rise density as its potential threat to the image of the city, its tourism industry, and the erosion of street-life. This straw man of “Manhattanization” has made the development of largescaled projects in San Francisco difficult and slow - empowering local organizations, neighborhood groups, and residents with political and procedural mechanisms to protest and stall new development. This continual extension of the length of time between speculation and construction of a new tower project has resulted in few high-rise projects whose collective number of units is failing to keep pace with demand. It is evident that this form of density is not able to effectively respond to the increasing growth and rapid market inflation of the city. Consequentially, density must find a different form and organization. Several diffused organizations of density have arisen in San Francisco that may offer alternatives to these more concentrated models. One of the more subversive forms of density that has emerged is one that embraces the Bay Area’s unique confluence of entrepreneurship, high technology, and countercultural spirit to leverage the might of Silicon Valley innovation to quickly, efficiently, and effectively re-wire the use of space in the city. In recent years, San Francisco has been the center for research on what has been termed ‘the sharing economy’, fueled by a wave of peer-to-peer experimentation and software apps that are challenging and reinventing the way in which we use the city. Peer-to-peer services such as Airbnb, Uber, Lyft and TaskRabbit (to name a few) utilize the notion of an economy of sharing to work within the gaps and blind spots of existing urban systems and regulatory frameworks to provide much needed services, and to better utilize the city’s vast but untapped latent capacity. Sitting within an ambiguous regulatory territory, the legitimacy of
URBANISM FROM WITHIN | THE URBAN WORKS AGENCY
such services is typically determined by local municipalities on individual rulings. As these companies have sparked a plethora of similar successful start-ups that respond to inefficiencies in the city, it is evident that while resistance is mounting by regulators and current providers, the novelty, effectiveness, and convenience of services that such software provides is too powerful to be overlooked in the long run. The success of peer-to-peer service lies in their acknowledgement of the limited resources of the city, and accordingly finding opportunism in sharing the hardware of the physical city. This could be compared to a re-mining operation that scans the original extraction site with new mechanisms, technologies, or policies to discover smaller amounts of previously ignored resources, which in aggregate, have a large value. As innovative as these peer-to-peer services are, they largely address the transient population of tourists and short-term residents. Yet, they have re-kindled an interest in another kind of re-mining operation that has been occurring in San Francisco for at least the last thirty years. One of the inadvertent outcomes of this housing crisis (and crises past) has been the widespread creation of secondary (in-law) units embedded within or located upon existing residential properties. Currently, the city estimates that over 50,000 illegal secondary units exist within the city limits; hidden in garages, attics, rear yards or underutilized spaces of homes. Because of their illegal status, these units have been largely unregulated, and most do not comply with current building, health, or fire codes. Further, the social and economic stigma associated with these unabashedly DIY domiciles has situated them in a difficult political territory for several decades. And yet, in March 2014, The Planning Commission of San Francisco gave unanimous support to legislation that would allow property owners in the Castro District to build secondary units in domestic buildings.4 This rapid shift in political winds went almost unnoticed, and though viewed as a pilot program, more legislation has since been proposed to legalize existing, and incentivize new construction of secondary units. What was once a marginal and almost completely invisible housing type may become an essential part
of the puzzle to address the current housing shortage. What is unique about the legitimization of secondary units is that while their mechanism for adding density is closely aligned with the premise of the sharing economy, their occupation is not necessarily temporal. These housing units remine the built fabric of the city, lodging themselves in underused garages, attics, or rear yards. As such, their presence is largely anonymous in the city, and it is this anonymity that makes them a subversive instrument for addressing the need for increased density. Without an apparent presence, there is little to protest, fear, or be threatened by. In fact, the presence of secondary units is largely felt in aggregate - on the pressures they exert on the city through increased density and its associated affects (the lack of open space, parking, increased traffic, etc.). Ultimately, as San Francisco’s history is intimately tied to how power from the top is redistributed to the bottom, the ability to address large scaled crises would inevitably need to arise from the bottom-individual residents and the spaces they occupy. Within the context of San Francisco, this could be the most effective tool to address density as well as the housing crisis. This paradigm shift toward a diffused form of density is radical because it signifies a transformation from hard to soft approaches in managing urban growth. Hard systems typically require centralized power, high capital expenditure, and failure in such systems is often catastrophic. The tower as a manifestation of a centralized form of density, allowed for by top-down city planning, and profited on by real estate developers, could be characterized within this vein. Conversely, soft systems are defined by similar terms to ecosystems - they are resilient systems typically comprised of a series of components that operate through complex feedback systems. The secondary unit as an aggregative approach aligns itself more closely with soft systems, offering individual choice to property owners to increase density in the city. Unlike Airbnb or other timesharing notions of the city, the secondary unit does not share time as much as space. The re-mining that is operative within the creation of secondary units relies more on the discovery
of the forgotten spatial products of San Francisco’s historic urban development, and the opportunistic re-allocation and enhancement of these sites into hybrid dwelling / utilitarian spaces. This positions design as a critical tool for advocacy - to reveal how small and typically underutilized secondary spaces can be reinterpreted into healthy domestic environments and to shift the culture of ownership of housing to multiple parties through more permanent and spatial forms of sharing. This legitimization of secondary units within the interior of the domestic fabric will require microtransformations to the architecture of the city- small artifacts and interventions that can mediate between the inner world of the interior and the external urban environment. More insidiously, such legalization will continue to exaggerate the polarization of an exterior expression of wealth and excess and an interior reality of an emerging urban proletariat. Yet, as the domestic fabric continues to be both limited and re-organized by capital, its interior can be rapidly and continually parsed to find new efficiencies and potentially new social arrangements. On its surface, the aim of the secondary unit is to increase the supply of housing stock and thereby decrease the cost of housing, with the ultimate goal of protecting and perhaps increasing socio-economic diversity. However, focusing on the unique typology of the secondary unit and its interaction with the larger systems of a city enables a deeper investigation into how a diffused form of individual interiors creates new connections, power structures, forms of sharing, crosspollenization of public and private realms, and formal architectural mutations. This close reading of the secondary unit not only interrogates the feedback mechanisms between the individual pixel of domestic space and the collective framework of the city, it implicates the interior in an investigation of how urbanism can be reformatted from within. THE INTERIOR AS A DEFENSE MECHANISM FROM THE URBAN ENVIRONMENT The parsing of the private architectural mass into a series of interiors that entail new forms of semi-shared spaces, blur the
distinction between the private and public realm. According to philosopher and cultural theorist Peter Sloterdijk, the apartment and its furnishings form an interior environment to sustain the well being of the occupant, and operate as a preventative measure against the disruptions of the shared public realm. Referring to the apartment as a spatial immune system, the domestic pixel supports the isolation of individuals and their life partners, allowing them to not collaborate in the community project.5 This requires the apartment to set limits to protect this inclusive exclusivity, as stated by Sloterdijk, “Immunity implies a prophylactic violence to prevent a harmful violence-it interiorizes what is wants to protect against.”6 Accordingly, architecture is employed as a defense mechanism to ignore the outside world by creating limits to demarcate the interior from the exterior. In a similar fashion, architectural historian and critic Marina Lathouri has revealed that the modern city as a concept was based on understanding individuality and privacy as separate from the notion of the public. In her assessment, the house was a private retreat from the external world, and, “in this process, the private effectively came to constitute the public, by marking its limit. What does it mean to label domestic space, public space, the space of the city, or national territory, if not to identify and define areas of interiority and proximity?”7 For both Lathouri and Sloterdijk, the limit is the expression of interiorized identity and creates a separation from the outside world. This limit as a tool of segregation and forming identity-is typically materialized by the architectural envelope. INTERIOR AS AN EXTENSION OF THE URBAN / URBAN AS AN EXTENSION OF THE INTERIOR The notion of the limit is intrinsically linked to separation, which was a critical spatial technique for sorting the city advocated by the C.I.A.M. group. In The Athens Charter and subsequent modernist texts, the pixel of the individual dwelling, or the unit, was positioned at one end of a spatio-political spectrum as the most basic element for reorganizing everyday life. The unit became the foundation for larger structural changes to the city and its culture as a whole.8 This inevitably shifted
one of C.I.A.M’s primary focuses to the relationship between the individual unit and the collective framework of the city. However, despite acknowledging the necessity of this relationship, the group still separated the study of an abstract notion of the individual from the complex framework of the city, as represented by the four elements of the Functional City (dwelling, recreation, work, transportation). Transportation infrastructure became an integral element of discussion in the latter years of C.I.A.M as an acknowledgement of its connective capacity to link and create relationships amongst the three other functional programs, and to establish an abstract framework for negotiating the individual and the collective. It was Team X, a generation of younger designers that joined and organized the latter discussions of C.I.A.M, that examined more closely how the domestic interior could be viewed as an associative space within the larger urban territory, mediated by the architectural envelope. Team X was interested in the continuity of experience from the interior to exterior, the private to the public. This space between these poles was associated and mediated through a plethora of architectural elements - the doorstep, windows, street, etc. - to produce a nuanced and porous series of thresholds. Reconceiving the original C.I.A.M Athens Charter through their Doorn Manifesto, Team X used the concept of habitat to situate the domestic unit as part of a larger geographic and cultural system.9 Developed through an adaptation of Patrick Geddes’ Valley Section, the manifesto was a ‘statement of habitat’ that examined how different forms of housing were intimately related to their geographic and industrial context. These varying contexts would be linked through a series of human associations between the interior and street, district, as well as city.10 This radical transformation on how to think about the city positioned the interior as an extension of the city, and the city as an extension of the interior. Moving beyond simple distinctions of interior/exterior, private/public, or individual/ collective, the group recognized that these elements were associated through a complex set of social, cultural, and spatial relationships that created and responded to an
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
STRATEGIC URBANISM THROUGH THE OPERATIVE LIMIT While the anonymous nature of the secondary unit is its most powerful weapon to address density in the city, this situates the domestic space as a defensive entity that does not integrate with the larger framework of the city. The limit is implicated here as an immunological defense system. Yet, the limit is also the threshold of providing expression to individual residents through form - enabling one to identify the space they have carved out within the city. Conversely, if the secondary unit is fully integrated within a network of urban associations, it is also at risk of losing its internal expression. Instead, we propose an operative limit as a mediator between how the secondary unit can precisely articulate its identity as well as associate with the larger urban environment. This is particularly important in the case of secondary units, as the space that is typically mined for secondary units is a result of the tensions between the persistence of the city’s grid and the variation in the city’s topography. This conflict between form and context has resulted in a series of deformations that instrumentalize the ground level as an inadvertent mediator between the formulaic consistency of residential typologies and the localized specificity of the topographic condition.11 This zone of interface between typology and topography has fostered an idiosyncratic series of ‘deformed spaces’- garages, storage, or service spaces - that the secondary unit is opportunistically poised to colonize. In material terms, this requires the engagement of the secondary unit with its street frontage as both the point of access and the main source of natural light. This sets up a design challenge where the
URBANISM FROM WITHIN | THE URBAN WORKS AGENCY
depth of the façade must limn the paradoxical need to both withdraw in a defensive manner from the city as well as opportunistically engage for its own internal functioning. Here, the façade as a limit is tasked to be both defensive and associative, and requires a material and tectonic articulation of the architectural envelope to mediate these connections. The typological catalogue that follows is an assemblage of case studies into this condition in San Francisco. It examines how to opportunistically leverage latent conditions in the city as well as refine the material transitions and separations between multiple scales of publics. Speculating on how to reconcile identity and anonymity, the case studies question how space and identity are parsed within the city. In aggregate, secondary units and their diffused form of density present a unique opportunity to test a bottom-up strategy for addressing the housing crisis, which most closely aligns itself within a discourse of ‘tactical urbanism’. We see this study as the first phase in longer discussion of how to mediate tactics with longer-term strategies for a renewed discourse on ‘strategic urbanism’. Not only are new modes of speculation required to understand the aggregative effects of these units on the city, a strategic framework is required to situate these units into the city. This meaning, the city is more than the sum of its individual residents and the units they inhabit. While the mediation and association of the private interior and public realm is precisely articulated through these proposals, it is still not clear how to manage the overall framework of the city with these units. How can these individual interiors be more than a grouping of units to create their own form of network and collective? How does this reorient the collective framework of the city so that there is reciprocity between these realms? The strategies that follow provide a first glimpse of how some of these issues can be reconciled and begin to frame a series of questions on their aggregative role in the city.
______________________________________
San Francisco Travel Association, San Francisco Visitor Industry Statistics, http://www.sanfrancisco. travel/san-francisco-visitorindustry-statistics (Accessed: February 2, 2015) 2 Lamb, Joonah Owen, Leveling SF housing field could take 100,000 new units, in: The San Francisco Examiner, (February 12, 2014) http://www.sfexaminer.com/ sanfrancisco/leveling-sf-housingfield-could-take-100000-new-units/ Content?oid=2703869 (Accessed: August 22, 2014) 3 Engardio, Joel P., Is rent control hurting San Francisco’s middle class? In: The San Francisco Examiner (January 5, 2014), http://www. sfexaminer.com/sanfrancisco/ is-rent-control-hurting-sanfranciscos-middle-class/ Content?oid=2665463 (Accessed: August 22, 2014) 4 Wiener, Scott and Board of Supervisors, Planning and Administrative Code - Construction of Inlaw Units, (February 11, 2014), http://www.sfaa.org/pdf/Castro_ In-law_Units_v2.pdf, (Accessed: February 4, 2015) 5 Sloterdijk, Peter. “The Apartment as Immune System” in SphŠren II: SchŠume. Frankfurt am Main: Suhrkamp Verlag, 2004. (534545) excerpted in Harvard Design Magazine 29: What About the Inside? Cambridge: Harvard Graduate School of Design, 2008. (49) 6 Ibid, 50. 7 Lathouri, Marina, The Necessity of the Plan’: Visions of Individuality and Collective Intimacies, in: Intimate Metropolis, ed. by Vittoria Di Palma, Diana Periton and Marina Lathouri, (London; New York: Routledge, 2009), (154). 8 Ibid, 162. 9 Ibid, 165. 10 Welter, Volker, Post-War CIAM, Team X, and the Influence of Patrick Geddes, in: CIAM Team 10-the English Context, ed. by D’Laine Camp, Dirk van den Heuvel, and Gijs de Waal (Delft: Technische Universiteit, 2003), (106-107). 11 Lipsky, Florence, San Francisco: The Grid meets the Hills (Marseille: Editions Parentheses, 1999), 99. 1
00 01
environment. This reading is more closely aligned with the increasing complexity of the contemporary city; its formal reification is now result of a negotiation between economics, politics, cultural values, and design, making separation and isolation of the individual formal elements of the city (house, street, block, etc.) not only difficult, but less relevant. Rather it is the relationships among the parts that is the critical mechanism for understanding both the components of the city as well as the overall system.
A B CONTEXT
RESIDENTIAL BUILDING PATTERNS
Many of San Francisco’s typical residential blocks derive from the original surveyed block - perhaps 200’ x 500’ or 200’ x 600’ depending on when the neighborhood was surveyed - being divided into 100’ x 100’ squares. Residential blocks were further subdivided into 25’ wide parcels. Imposing rear yard setbacks and height limits results in the building patterns found throughout the city.
HISTORY OF ADU DEVELOPMENT IN SAN FRANCISCO
ADUs IN SAN FRANCISCO TODAY
HOUSING TYPES AND ADUs
Accessory Dwelling Units are not a new housing solution; in fact there are many ADUs in the City’s existing housing supply. In some neighborhoods, the original houses from the 1800’s were built far back from the street and new larger buildings were built in front, turning the original dwelling into a backyard dwelling. In many other places garages or ground floor storage rooms were long ago turned into a separate apartment.
There are a wide variety of housing types in San Francisco, but many of them share the common feature of a raised first floor, with surplus space at ground level often used for storage or extra parking. Buildings built in the first half of the twentieth century, which makes up the majority of the City’s housing stock, often had parking at the front of the building with additional rooms behind the garage. This is true for both single family homes, and two and three family apartment buildings. Even older buildings built without garages were often raised to build a fullheight garage at some point in the last century, often creating surplus space at the ground level that could be turned into an ADU.
Some of these units were established before the City closely regulated such activities. Others were created with Planning and Building Department review, and some were built without the proper permits and approvals.
Since the early 1980s, the State of California has encouraged municipalities to allow ADUs to help meet local housing needs. State legislation around secondary units has been amended frequently over the years, but continues to compel municipalities to allow secondary units.
These ADUs, commonly referred to as “illegal units” provide a valuable source of housing for San Francisco’s existing residents. Previously, if the Building Department received reports of illegal units, they were legally obliged to issue a Notice of Violation and require the property owner to demolish the unit. The legalization program now allows property owners to permit and secure existing ADUs which meet the City’s building and fire standards. This allows property owners to clear their property record. Furthermore, it insures that tenants can stay in a safe and secure unit.
LEGALIZATION OF EXISTING ADUs
Recently the City created a new program which allows property owners to “legalize” existing ADUs that either do not have a permit history, or were built without the appropriate permits.
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
PROTOTYPE A
REAR YARD
1
4
PARTIAL GARAGE CONVERSION IN A SINGLE-FAMILY HOME BEDROOM
The existing building is one of the more common housing types in San Francisco - a two-story single-family home with an open garage on the ground floor, and all of the living space and bedrooms upstairs. These buildings are generally twenty five feet wide, filling the entire width of the typical San Francisco parcel; and leaving no room for a side yard.
LIVING ROOM
ADU STRATEGY
2
The unit plan assumes at least one on-site parking space will remain, and that the existing footprint of the house will be maintained. The unit is arranged at the rear of the ground floor, with the living space and bedroom placed against the exterior wall to take advantage of the natural light and ventilation. It is likely that the upstairs bathroom and/ or kitchen are located towards the middle of the plan as well, hopefully allowing for a relatively easy access to service lines. San Francisco will not permit a dwelling unit to exit directly through a garage, so a dedicated exit hall has been built inside the garage leading from the rear unit to the tradesman door at the front.
5
EXISTING GARAGE
3
UNIT PLAN 1. Bedroom and primary living space are arranged to maximize access to natural light, with operable windows and doors facing the rear yard. 2. Provide a fire-rated wall to separate the dwelling unit from the garage. 3. Fire-rate the new exit hall through the garage that leads from the unit entry door to a door that opens directly to the sidewalk. 4. Emergency escape and rescue openings to the rear yard. 5. Provide a fire-rated door between the garage and the exit hall.
CONTEXT | OPENSCOPE
A
A B C POLICY
HOUSING POLICY AND ADUs
In relation to ADUs, the Planning Department is generally interested in whether additional units are permitted (density), while the Building Department is concerned with the life safety issues of a unit. Most of the policy work around the inclusion of ADUs happens through changes to the Planning Code.
is common in many California jurisdictions, and consistent with State policies. Historically less than fifty properties in San Francisco had this designation, however in 2014, as one of the many responses to growing housing affordability issues, the City expanded this program to the Castro Area.
San Francisco currently allows ADUs in many parts of the City. Many properties are not built to their maximum allowable residential density. For example, a lot may be permitted to have three units, but only has one or two. These properties are permitted to add additional units, that may be full units, or “accessory” units.
The City can continue to make it easier for property owners to understand the costs and benefits of adding an ADU to their property. This research, Zoning Administrator Bulletins, Building Department Bulletins, and ongoing improvements to City review processes can help facilitate the addition of ADUs.
Many of the newer zoning districts, replacing thirty year old zoning controls, have removed the residential density limit. Instead, these zoning districts are regulated by building height, bulk, rear yard, and open space requirements. Often these districts also require a mix of unit sizes. These properties can add additional units, including ADUs.
The City can continue to identify unique opportunities to enable property owners to offset the costs of maintaining their homes through the addition of an ADU. There has long been discussion about pairing the addition of ADUs with seismic upgrades, especially for soft story buildings. The City can adopt recently proposed legislation, which enables property owners to seismically secure their home while adding an ADU.
There are some zoning districts that allow property owners to go above their maximum density by adding an accessory dwelling unit - RH-1(S) in particular. This type of regulation
a neighborhood’s housing supply. Communities with aging populations, high numbers of college students, or homeowners struggling to meet their housing costs might benefit from the ability to add ADUs.
Also, the City can work with communities to determine where ADUs would be an added benefit to
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
PROTOTYPE B
REAR YARD
6
5
LIVING ROOM
PARTIAL GARAGE CONVERSION IN A DUPLEX
7
The existing building consists of two flats over an open one-story ground floor garage. Unless the site is on a steep uphill slope, the garage is typically large enough to park two cars in tandem, and still have room for storage along the rear wall. A narrow side yard often provides access from a tradesman door to the backyard. The units above may extend over a portion of the side yard, but the majority of this space is open to the sky and functions as a lightwell. There is a single shared entry stair leading up from the street to a common landing at level two. Access to the upper flat continues up a second interior stair. There is often a secondary stair near the rear of the building that gives one or both of the units access to the rear yard and side yard/lightwell.
3
KITCHEN
BEDROOM
2 4
ADU STRATEGY
1
To maximize opportunities for natural light and ventilation in the living and sleeping spaces, most solutions plan for the kitchen and bathroom to be brought as far into the middle of the building as is feasible. This design has moved the bedroom behind the main living space, separating them with partial-height walls so that natural light can be shared between both rooms.
EXISTING GARAGE
8
Unit Plan 1. Lightwell with upgraded fire-resistance for an exit court 2. Vestibule to separate dwelling unit from the garage 3. Fire-rated wall between the unit and the garage 4. Fire-rated door between the unit and the garage 5. Emergency escape and rescue opening to the rear yard 6. Access to natural light and ventilation
A B
7. Bedroom shares light and ventilation with the living space 8. Existing door with at least 32� of opening width
POLICY | OPENSCOPE
C D ZONING
San Francisco has over 200,000 parcels of property. Of those, approximately 167,000 parcels are currently zoned for some level of Residential or Mixed-Use Development. Over 75,000 of the Residential parcels are reserved for singlefamily homes with RH-1 and RH-1(D) designations. Increasing the unit count on single-family lots - through the addition of an Accessory Dwelling Unit or any kind of unit - is prohibited under the current Zoning Code, unless the unit is specifically designed for, and occupied by, senior citizens. Legislative pilot projects are beginning to explore a set of wider exemptions to density restrictions for ADU’s, but this has yet to be implemented city-wide.
SAN FRANCISCO ZONING CODE
The first step to understanding whether you can build an ADU is to understand the zoning of the property in question. Zoning regulations govern how land can be used in various geographic areas of San Francisco called “zoning use districts”. For example, zoning regulations might: govern sizes and shapes of buildings, limit the number of units or apartments that can exists on a property, require the accommodation of car parking off of the street, set controls on planting street trees under certain circumstances, and specify how late a business can remain open at night. For each use, zoning regulations are specified in detail in the “San Francisco Planning Code.” For each type of use, the Code specifies it’s either: Permitted (P), Conditional (C), or Not Permitted (NP). Knowing the zoning of your property will help you understand what’s allowed, and what specific limits may apply to your residential or commercial project.
Rules for each zoning designation outline property height limits and setbacks, as well as how many dwelling units are allowed on a site in a residential district. For example, in RH-2 zoning up to two units per lot are currently allowed. In other zoning types, the number of units is
determined by the area of the building lot. In a Residential, Mixed District (Houses & Apartments) like RM-3, one unit per 400 square feet of lot area is permitted.
that increase the overall required parking count by two or more spaces. Adding a single ADU would not require an additional parking space anywhere in the city.
Many parcels are currently underdeveloped relative to the existing zoning. For example, a homeowner of a single family home in an area zoned for two-family buildings (RH-2 zoning) would be able to to add an additional unit within the existing zoning of the property, as long as the other regulations pertaining to setbacks, height, and parking are followed.
The number of car parking spaces on site may be reduced if they are replaced with Class 1 bicycle spaces (secure and sheltered). You may be required to add bicycle parking for the ADU.
ZONING AND DENSITY CONTROLS
Many parts of the city have been rezoned in recent years, and some of the new zoning designations do not have density controls. This means that as long as you follow the other regulations the city has set forth regarding height and setbacks that dictate the building’s size, there is no limit on the number of dwellings that can be on the lot. PARKING REQUIREMENTS The Planning Code requires one parking space per residential unit in most neighborhoods. Additional parking is only required for renovations
SETBACKS Setbacks determine how closely structures may be built to a property line. Many existing buildings are built to the side and front property line in San Francisco. Calculating the setbacks with an addition to the rear of a house can be tricky because it can depend on the location of the rear wall of the neighboring properties. One important item to note is that in almost no case will you be allowed to build an addition or new structure in the last twenty five percent (or 15’ minimum) of your property. In some zones the rear yard requirement can be as high as forty five percent of the overall depth of your lot.
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
PROTOTYPE C PARTIAL GARAGE CONVERSION IN AN APARTMENT BUILDING
EXISTING GARAGE
This model takes place in an older low-rise apartment building common throughout much of the city. These are typically three or four stories, and have at least six units. They are often found on corner lots, and may have quite a few parking spaces immediately adjacent to the sidewalk - with the cars either concealed behind separate garage doors, or exposed in open carports. ADU STRATEGY A single parking space may be smaller than the 220 square foot minimum required for an efficiency unit. If there is not sufficient area in and around the parking space to accommodate the unit, two on-site parking spaces may need to be removed - as is shown in this example. With the building on the corner, the one-bedroom unit was placed to be able to take advantage of being able to get light from two sides, with the living room and kitchen extending nearly the full depth of the building.
3 BEDROOM
2
LIVING ROOM
1
UNIT PLAN 1. Replace garage door(s) with a swing doors and windows. 2. Ensure that the bedroom and other sleeping spaces have adequate access to windows for light and ventilation; and for emergency rescue openings. 3. A fire-rated wall is required between the dwelling unit and any garage or storage space.
ZONING | OPENSCOPE
B C
D
BUILDING CODE
CALIFORNIA BUILDING CODE
Understanding the basics of the building code is one of the keys to determining the feasibility of a renovation project, especially when it comes to adding an extra housing unit on your property. In San Francisco, the Department of Building Inspection (DBI) enforces the California Building Code and is responsible for issuing building permits, conducting construction inspections, and tracking code violations. TYPE OF OCCUPANCY One key feature of the Building Code is that it categorizes how buildings are used in order to determine applicable requirements for exiting, fire safety, construction materials, etc. The buildings most commonly considered for adding a secondary dwelling unit generally will fall into either the R-2 or R-3 Occupancy Group. An R-2 occupancy has more than two dwelling units, while an R-3 has two or less. Taking an existing building with two units and turning into a three unit building will change its occupancy from R-3 to R-2. In short, an R-3 building is viewed from a code perspective as a single family home while an R-2 building is viewed as an apartment building.
MEANS OF EGRESS The Means of Egress is the entire exit route from an occupied space to a public street. It can include stairs, ramps, doors, and passageways that are all defined in the code and are required to have specific construction requirements (generally to prevent the spread of fire). FIRE SAFETY Increased fire safety is achieved by both passive and active methods. One of the most direct passive methods that the Building Code uses to reduce the risk of fire is to require that fire resistant materials be used in the wall assemblies that separate different spaces. Fire sprinklers are an example of active fire protection, and are now required in all new residential construction in California. INSIDE THE UNIT The main living space and the bedroom must have 7’-6” minimum ceiling heights. The other rooms in the unit - kitchen, bathroom, hallways, laundry rooms - can have ceilings as low as 7’-0”. Headroom is typically quite low
when dealing with adding ground floor units to hillside properties, or in existing garages - and there are a number of exceptions for beams and sloped or furred ceilings - so clearances should be should be reviewed during the preapplication meeting. The Building Code has a specific category for an exceptionally small studio unit that has one space used for sleeping, cooking, eating, and living space. The total area of the unit (including bathroom, closets, kitchen, and all living and sleeping space) must be at least 220 square feet. The unit is limited to two occupants, and an additional 100 square feet of unit area must be provided for each occupant over this two-person limit. The primary living space must at least 150 square feet. Building codes require that all habitable rooms are provided with adequate levels of ventilation and natural light. In a studio apartment unit that is one room, the floor area of the entire living and sleeping space needs to be used to calculate the light and ventilation requirements.
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
PROTOTYPE D
REAR YARD
4
2
FULL GARAGE CONVERSION IN A SINGLE FAMILY HOME Similar to Prototype A, this type is intended to cover a single-family residence that would be common throughout many parts of the city. As we will be converting the entire ground floor for the new dwelling unit, we have a selected a common Junior-5 plan which is shallower (typically only 35’ deep) than the larger barrel-front and patio-plan homes. These smaller footprints tend to be represented in a slightly newer housing stock than the larger plans, with variations on this type being common from the 1940’s onwards.
BEDROOM
LIVING ROOM
ADU STRATEGY This plan utilizes as much of the ground floor as possible, while allowing that some space will usually be needed for the furnace and water heater that serve both this unit and the upstairs unit. There are many configurations of two-bedroom units possible in this footprint. This particular layout assumes a relatively quiet street that would allow for a bedroom next to the sidewalk. Other variables such as rear yard amenities, views, sloped sites could suggest different arrangements of living room, kitchen, and bedrooms.
BEDROOM
3
1
2
UNIT PLAN 1. Replace the garage door with a swing door and windows. 2. Each bedroom has access to natural light, and the possibility of operable windows for ventilation 3. New screening enclosure for trash, recycling, and compost receptacles. 4. Covered and secure bike parking
BUILDING CODE | OEPNSCOPE
C D
01 02
THE THICKENED WALL Type: Victorian Neighborhood: Haight Location: Haight and Ashbury Average Studio Rental Price: $3,000 Block Size: 275 ft x 412 ft Number of Lots: 36 Lot Size: 100’ x 137.5’ Typical Parcel Size: 27.5 ft x 100 ft Zoning Height: 40 ft Also found in: Mission, Noe Valley, SOMA Historic Sq ft: 5.740 Present Sq Ft: 5,740 Proposed Sq Ft: 6,640 ADU Sq Ft: 900
190
75
a var
var a
20'
5 0' x
20
BLOCK
04'
1 0' x
10
LOT
6’
2 0’ x
10
PARCEL
OPEN SPACE
40'
01
HEIGHT
N
While the Victorian House is often a site of exploration for secondary units, these are typically designed within garage spaces. The gabled roof on several of these types provides a forgotten space to be recouped within the envelope. This is particularly important as the majority of these types occur in zero-lot line conditions, making other modifications or additions that often transpire on the ground floor difficult. There is a large prevalence of this type in San Francisco’s Haight District. Given the amenities, location, access to public transportation, and culture of this neighborhood, it attracts an emerging demographic that privileges geography over amount of space. The largest challenge to accommodating new secondary units within an attic space is access. Due to the zero-lot line condition, the circulation space must be negotiated within the interior of the house. This case study proposes to continue the circulatory logic of the existing type, which organizes its corridors and vertical circulation along the party wall, to the attic. The other difficulty within attic spaces is the lack of height, particularly along
the lot line where the roof meets the floor. Accordingly, this proposal examines how a linear secondary unit can be designed that utilizes a thickened wall that activates a central axis. Integrating storage, closets, furniture, and service spaces into this edge condition, the central spine is continually being redefined by how the thickened edge unfolds, slides, shifts, or rotates into this space. This approach focuses on how to optimally organize domestic program based on varying height to recoup what is typically considered unusable space. By consolidating these programs and their physical artifacts within the thickened wall, the central space is highly flexible and can be rearranged during different times of the day or by distinct inhabitants.
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
H
CL
AYT O
NS
T
THE THICKENED WALL | CHRISTOPHER BAILE
T
TS
H AIG
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS light access open
INTENDED USE 1906
MODIFIED USE 2015
73 lf built
25’ 137’-6”
third floor light access open
light access 27’-6”
open
75 lf built
second floor
second floor
first floor
first floor
garage
garage
78 lf built
100’
light access open
light access open
25’
79 lf built
73 lf built
25’
137
137
’-6
’-6
”
1906
”
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
KITCHEN PRIVATE ENTRANCE DORMER EXPANSION BUILT IN STORAGE
SLEEPING AREA
00 01 SHARED ENTRANCE
THE THICKENED WALL | CHRISTOPHER BAILE
02 03
THE HORIZONTAL CORE Type: Front Yard Addition Neighborhood: Castro Location: Diamond and 18th Average Studio Rental price: $3,000 Block Size: 250 ft. x 500 ft. Number of Lots: 8 Lot Size: 125 ft. x 125 ft. Typical Parcel Size: 125 ft. x 24 1/2 ft. Zoning Height: 40 ft. Also found in: Those neighborhoods with sloped terrain Historic sq. ft.: 1450 Present sq. ft.: 1800 Proposed sq. ft.: 1800 ADU sq. ft.: 650 ea.
90
180
a var
var a
00'
5 0' x
25
BLOCK
’
125
’
25 X1
LOT
'x
125
6”
24’
PARCEL
OPEN SPACE
HEIGHT 40'
02
N
The Castro District is the first neighborhood in San Francisco to encourage new secondary units. With the aim of addressing a growing aging population in the neighborhood and a need to age-in-place, this case study examines how new on-grade units can support a multi-generational family. The chosen Victorian type is common in the Castro District and is typically arranged on a long linear parcel. With the topographic variations in the Castro, several of these houses are situated on steep, upslope lots. Because of this, a large exterior stair is required for inhabitants to access their house, which is nearly a level and a half above grade. A minimal front yard setback dictates that the exterior stair protrudes substantially from the house, turning at a landing and continuing parallel for some distance along the front of the house. This technique to allow for access with a small setback creates a terracing on the street that can be adjusted to provide entry to the unit above as well as natural light for the unit below.
By partially excavating the back of the parcel, it allows for increased natural light and a separation of the backyard for two distinct inhabitants. With a redevelopment of the front entry and back excavation, a large amount of light can be achieved in the secondary unit. Moreover, the large ceiling height, a rarity for most secondary units, can be leveraged into a three-dimensional programming of the space. This case study examines how natural light can be efficiently distributed in the space along with three-dimensional programming, to create highly functional micro-units. This occurs by separating the long, linear unit into a flexible, open, and unprogrammed space as well as an articulated, three-dimensional, fixed, program space.
The linearity of the parcel promotes a larger, open unit to maximize sunlight. URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
M
D ON
DIA 18T
HS
T.
THE HORIZONTAL CORE | JARED CLIFTON
ST.
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS
light access 24’-6”
open
INTENDED USE 1900
MODIFIED USE 2015
first floor
first floor
garage
garage
70 lf built
125’ light access open
light access open
light access open
The case study leverages the existing light well in the unit and reconceives of this shaft as a courtyard that would divide the linear plot into two secondary units. Utilizing large, glazed roll-up doors within each unit enables a continuous space that still has the potential for privacy. This continuous space is flexibly programmed with mobile furniture to allow for a variety of activities that can be adjusted to the inhabitant and
83 lf built
83 lf built
89 lf built
the different events of their lives. When the roll-up doors are closed, the space can be subdivided into two discrete units that share the central courtyard. The doors enable the finetuning of the space — interconnected, partially connected, and separated, to align with differential familial relationships. Subsequent programs are packed into a horizontal core running along the party wall. This programmed tube takes advantages
of the large ceiling height to organize storage, sleep, service spaces, and working areas along two levels. The backyard is excavated and terraced to allow for an outdoor space for the new and existing inhabitants. The aim of the case study is to propose new ways to organize micro-units through highly flexible and controlled spaces to facilitate how multi-generational families can age-in-place.
6”
6”
’24
’24
’
’
125
1900
125
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
STUDIO
COURTYARD
STUDIO
UPPER PATIO
01 02
UPPER CLOSET SLEEPING
LOWER PATIO
LIBRARY
LOWER CLOSET
LIBRARY
BATH
SLEEPING KITCHEN
UPPER CLOSET KITCHEN BATH LOWER CLOSET
THE HORIZONTAL CORE | JARED CLIFTON
03 04
THE PRIVATE PARKLET Type: Victorian Neighborhood: Castro Location: Noe and 18th Street Average 2 Bedroom Rental price: $3,859 Block Size: 285 ft x 540 ft Number of Lots: 44 Lot Size: 25’ x 125’ Typical Parcel Size: 25 ft x 125 ft Zoning Height: 40 ft Also found in: Richmond, Sunset, Mission, Pacific Heights, Historic Sq Ft: 2,553 sq. ft. Present Sq Ft: 3,405 sq. ft. Proposed Sq Ft: 4,155 sq. ft. ADU Sq Ft: 750 sq. ft.
100
03
a var
0
20
ra va
5'
28
x
N
0'
54
BLOCK
x 0'
10
5' 12
LOT
'x 25
5' 12
PARCEL
OPEN SPACE
40'
Several of the Victorian Houses in San Francisco’s Castro District have been redesigned from the interior over the years to allow for multiple apartment units as well as parking. This case study examines a typical house on Noe and 18th street. Originally built in 1900, the home was intended for single-family occupancy, but development pressures and the opportunities of a growing rental market has altered its interior arrangement. The original house was designed with a service corridor on grade level to access the backyard and storage spaces. Since its initial conception, the house has leveraged this corridor and stair circulation to divide the space into two apartment units, each comprised of two bedrooms as well as a small secondary unit that gains natural light from the backyard. The resultant garage space was excavated from the front of the parcel to allow for driving clearance by avoiding the entry stair to the house above. Accordingly, this formed an unusually high ceiling height in the garage, which is optimally set-up for an additional secondary unit. The confluence of the service corridor, topography,
and entry stair clearance, sets the framework for colonizing the garage space with a secondary unit that has a separate entry as well as high ceilings. The design that follows utilizes a sectional terracing of the space to accommodate a highly efficient two-bedroom apartment. Further, the grade separation provides a large degree of privacy despite the open street façade, which is opportunistically programmed with a private parklet.
HEIGHT URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
N OE
18 TH
ST .
. ST THE PRIVATE PARKLET | TYLER JONES-POWELL
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS light access open
INTENDED USE 1900
MODIFIED USE 2015
72 lf built
100’
light access
100’
open
87 lf built
125’
30’
light access 125’
open
light access open
25’
The secondary unit utilizes a series of thin walls set within the space to create a porous technique to modulate privacy. Private sleeping spaces are elevated and straddle between these walls, forming a complex three-dimensional arrangement of the space. Offset from each other, these sleeping
second floor
first floor
first floor
garage
garage
68 lf built
25’ 70’
second floor
76 lf built
units separate the service and public space of the apartment. A glazed garage door sits within the existing framework to draw in natural light and extend the living spaces in to the exterior private parklet. This parklet is exposed to the street, yet protected by the entry stair above. While the secondary unit consumes
garage space that once hosted up to three vehicles, due to the steep slope of Noe Street, these are recouped as on-street perpendicular parking spaces. Ultimately, this case study examines how to utilizes specific design decisions to allow for a field of flexible occupational strategies.
’ 25
’ 25
’
’
125
1904
125
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
BATHROOM LOFTED BED KITCHEN DINING / LIVING TERRACE ENTRANCE
THE PRIVATE PARKLET | TYLER JONES-POWELL
02 03
04 05
THE PUBLIC INTERFACE Type: Multi-unit Building Neighborhood: Lower Haight Location: Waller and Pierce Average Studio Rental Price: $2,460 Block Size: 275 ft x 410 ft Number of Lots: 8 Lot Size: 100’ x 135 Typical Parcel Size: 25 ft x 140 ft Zoning Height: 40 ft Also found in: Western Addition, NOPA, Mission, Pacific Heights, Nob Hill, Marina Historic and Present Sq Ft: 2915 Proposed Sq Ft: 2915 ADU Sq Ft: 435, 318 and 418
0
10
a var 0 15
04
ra va
00'
4 0' x
28
BLOCK
00'
1 0’ x
14
LOT
5’
2 0' x
14
PARCEL
OPEN SPACE
40'
HEIGHT
N
The multi-unit apartment building is a common type found on corner parcels in San Francisco. Because of the linear geometry of San Francisco’s parcel division, the corner lot is often arranged to be parallel to the block. Accordingly, these lots are unique in that their buildings are not reliant on the back or side lot for natural lighting. This allows the resulting type to efficiently arrange units along the street with minimal cutouts, recesses, or light wells. Further, this is one of the few building types in San Francisco that lends itself to street access, which has typically been dedicated to private parking. As a result, several of these buildings have a soft-story and are not seismically fit. Leveraging the soft-story program, this case study examines how to redevelop these garage spaces into a series of unit types that have differential public interfaces.
was originally conceived as multifamily housing and therefore each unit has a private entry. With the separation of parking from the unit’s above, the building is conducive to new secondary units that have direct private access from the street without intruding into existing units and their access. The two largest challenges with this ‘recovered’ space is the distribution of natural light due to low ceiling heights and unit depth, as well as mitigating privacy from the surrounding busy streets. This challenge is common among several secondary units — how can the unit be designed to gather natural light from the street, while still providing the inhabitant privacy from the same street?
The case-study type is a six-unit, fourstory building located off the Duboce Park and within walking distance to key public transportation networks (N-line, buses, bikeway and highway) as well as several public amenities. This multi-story apartment building URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
ST . R LE W AL PIE
RCE
ST.
THE PUBLIC INTERFACE | BELLA MANG
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS
INTENDED USE 1900
light access
25’ 100’
30’
open
188 lf built
100’
50’
100’
85’
MODIFIED USE 2015
third floor
third floor
second floor
second floor
first floor
first floor
garage
garage
140’
Three units were developed to test different levels of privacy for a young creative single or couple that can benefit from a centralized location. Each unit is equipped with one mobile element that can be adjusted to control the level of privacy in the unit. Unit 1 The corner unit allows for more public interaction with the street and is developed as a live/work/retail space along with a public parklet. A large shelving system on rails serves as a privacy screen, workstation, and retail display during the days, and window display during the night. Unit 2 This small, 318 square foot unit uses a horizontal surface as a workstation adjacent to the street during the day and a dining table during the evening. The rest of the unit’s facilities for living are provided within a singular central furniture piece that accommodates kitchen, dining table, and seating. Unit 3 This bounded unit proposes a more secluded living space with a small veranda for a semi-private outdoor terrace. As the large window opens, the indoor program such as dining areas, are situated on the protected exterior.
0’
10
25’ 1900 and 2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
UNIT 1
THE PUBLIC INTERFACE | BELLA MANG
UNIT 2
UNIT 3
03 04
05
THE LIFTED GARDEN Type: Marina Style Neighborhood: Bayview Location: La Salle and Newhall Stv Average Studio Rental Price: $1,000 Block Size: 200 ft x 600 ft Number of Lots: 51 Lot Size: 100’ x 104’ Typical Parcel Size: 26 ft x 100 ft Zoning Height: 40 ft Also found in: Sunset, Richmond, Outer Mission Historic Sq ft: 1,340 Present Sq Ft: 2,000 Proposed Sq Ft: 2,500 ADU Sq Ft: 500
75
a var 0 22
x 00'
2
var a
05
'
600
BLOCK
N
x 00'
1
'
100
LOT
5’
2 0' x
10
PARCEL
OPEN SPACE
HEIGHT 40'
The neighborhood of BayviewHunter’s Point, first developed around its massive shipyard, experienced a surge in economic growth during WWII. Post-war, lacking a demand for Naval ships, the neighborhood’s primary economic driver shut down, and with it the suburban development fell to neglect. As one of the least expensive neighborhoods of San Francisco, it has long received the city’s otherwise rejected inhabitants. Today a prime location for both students and families seeking affordable rent, it is expected to experience an economic revival as the UCSF Mission Bay campus expands. The most ubiquitous housing type in the Bayview is the two-bedroom Marina style, which is characterized by a wide, rounded bay window and stair access to a gated second floor entry. These units are almost always above a one or two car garage and occupy a minimal footprint of just over fifty percent of the lot area. This housing type, found not only in the Bayview district, is ideal for rear-yard additions.
its garage into an additional unit, and seeks to add density to the neighborhood while respecting its appreciation for private outdoor space. To do so, the backyard is ‘peeled up’ and an ADU is inserted beneath, resulting in an artificial topography. Sloping this way would not only allow light and fresh air to the existing building, but would serve as a terraced garden for the upper unit to access and occupy creatively. Where the slope meets the ground, it is lifted for clearance, thereby providing a protected patio for the garage conversion. The sloped ADU would only occupy twenty five percent of the lot and therefore receive the remaining twenty five percent of existing yard.
This particular design takes on a residence that has already converted URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
A AS
LL
L
NE
WH
AL
LS
T
THE LIFTED GARDEN | BLAKE STEVENSON
VE. A E
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS light access open
light access 25’
open
100’
light access open
INTENDED USE 1927
MODIFIED USE 2015
140 lf built
110 lf built
120 lf built
first floor
first floor
garage
garage
30’ 100’ light access open
light access open
Given the proportions of the garage / storage space on the ground floor in the original house, several of these Marina typologies have already converted the rear portion of this space into a secondary unit. An existing service corridor is used to access this unit, and this same circulation space provides access to an outdoor walkway to the proposed secondary unit. This ensures private entry as well as a street address for all three inhabitants. Additional
120 lf built
110 lf built
natural light has been achieved in the existing type through two light lights wells that create a dumbbell plan configuration. Because of the consistency of this type, the light wells of adjacent units align to create micro-courtyards. The proposed secondary unit, however, employs a different approach to ensure adequate light to these two units from the rear yard. The unit slopes downward towards the existing house to optimize light and fresh
air to the existing units, and orients itself away from these units towards the rear of the parcel. This produces a new typology of the rear yard that utilizes the slope of the secondary unit to create a terraced garden. What results is the transformation of a single-family residence to a parcel that is reconfigured for three inhabitants that each has private access, light, and a garden.
’ 25
’ 25
’
’
100
1927
100
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
UPPER UNIT TERRACED GARDEN
04 05
ADU BACKYARD
LOWER UNIT PATIO
PRIVATE ENTRANCE TO GROUND FLOOR UNIT + ADU
THE LIFTED GARDEN | BLAKE STEVENSON
06 07
THE DOUBLE DECKER Type: Mission Victorian Neighborhood: Mission Location: Bryant and 22nd Average Studio Rental Price: $2,498 Block Size: 200 ft x 520 ft Number of Lots: 10 Lot Size: 100’ x 104’ Typical Parcel Size: 26 ft x 100 ft Zoning Height: 40 ft Also found in: The Haight, Noe Valley, SOMA, The Castro Historic Sq ft: 2,500 Present Sq Ft: 2,500 Proposed Sq Ft: 3,175 (overall) ADU Sq Ft: 675
75
a var 0 19
'
200
var a
'
20 x5
BLOCK
N
04'
1 0' x
10
LOT
00'
1 6' x
2
06
PARCEL
OPEN SPACE
In little more than a decade, the Mission District has become one of the most expensive and sought after residential neighborhoods in the city. Due to its central location in San Francisco, vibrant food and arts culture, open space resources, and easy access to transit, the Mission has become an emblematic battleground between long-time residents and recent gentrification. The only solution we are left with to lower housing costs in this neighborhood is through the addition of density. The building lot and footprint examined in this case study is an extension of the rectangular logic of the vara, which originally subdivided the city’s blocks. The Victorian threestory pitched-roof home with entry and interior hallways along one side of the lot is one of the most ubiquitous of San Francisco housing types. This building type typically situates the garage a half-story below grade, with each linear floor sectioned to allow each room access to sunlight and air. Rear-yard access is typically enabled through an interior hallway, which allows the building to maximize it’s buildable footprint on the lot.
As time has progressed and housing pressures have mounted, the singlefamily townhouse has been densified and subdivided. Living rooms were converted into bedrooms, a rear study was transformed into a new kitchen, and staircase access was segregated from the living spaces to allow individual units access from the first floor. The incremental changes doubled use of the single-unit, twobedroom house and converted it into a two-unit property with four bedrooms in total. As need has increased again, this case study proposes a continuation of this opportunistic trend to construct three discrete units on a single parcel.
HEIGHT 40' URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
NT RYA
B
22N
DS
T
THE DOUBLE DECKER | SHAWN KOMLOS | JEFF MAESHIRO
ST
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS light access open
INTENDED USE 1906
MODIFIED USE 2015
second floor
second floor
first floor
first floor
garage
garage
72 lf built
25’ 100’ light access open
light access 30’
open
100’
78 lf built
93 lf built
light access open
light access open
Entered from a service corridor connected to the house’s street frontage, occupation of this secondary unit is oriented primarily towards the lot’s rear yard. Domestic spaces are layered inward from the back face of the house, and all spaces have access to the resources of light and the exterior terrace. An extension to the existing building footprint pushes a new volume into the yard. Contrary to conceptions that adding a unit to a lot would constrict the
97 lf built
92 lf built
existing dwellings, this design both increases density on-site while also adding to the existing first floor unit. This mutual benefit takes place in the form of a deck, which is stacked on top of the bedroom extension of the new ground-floor unit. This allows for a generous outdoor seating area to a unit which previously only had windows looking into the yard. Moreover, this allows multiple users to access exterior space.
With access on two sides to a private patio, this extended space shares its ample light with the living spaces deeper in the house through a translucent screen wall, the borrowed daylight augmenting direct access to light and ventilation in the house’s side-lot cutouts. Careful treatment of light allows for the dual benefit of extended amounts of space and comfortable natural lighting deeper in the partially below grade basement.
’ 25
’ 25
’
’
100
1904
100
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
BACKYARD PATIO BEDROOM KITCHEN AREA
DINING / LIVING PRIVATE ENTRANCE
THE DOUBLE DECKER | SHAWN KOMLOS | JEFF MAESHIRO
06
07 08
THE MICRO-VERTICAL Type: Mission Edwardian Neighborhood: Mission Location: Treat and 23rd Average Studio Rental Price: $3,400 Block Size: 244 ft x 520 ft Number of Lots: 33 Lot Size: 30’ x 122’ Typical Parcel Size: 30 ft x 100 ft Zoning Height: 40 ft Also found in: Castro, Lower Haight, and Western Addition Historic Sq ft: 5250 Present Sq Ft: 5590 Proposed Sq Ft: 5590 ADU Sq Ft: 340
90
va ra
190
244
'x5
var a
20'
N
BLOCK
122
'x9
0'
LOT
122
07
'x3
0'
PARCEL
OPEN SPACE
40' HEIGHT
The Edwardian typology is typically located on wider San Francisco parcels, that allow for both a continuous interior and exterior circulation route. This enables an efficient plan that arranges a series of rooms in a linear fashion along the corridor. Originating as a multi-unit residence aimed at housing incoming working class immigrants to the city, the majority of these types have been easily converted into a denser series of three or four-bedroom apartments due to the continuous access. This case study examines a house in the Mission District — a neighborhood facing pressures to find innovative forms of density — to understand how a new series of secondary units could stymie proposed high-rise condominium development.
shifted the perceptual territoriality of the rear yard to the units with direct access. This case study investigates how to redesign the rear interface of the house to ensure fire and building code requirements as well as to enhance the exterior rear yard for communal use by all tenants. The mechanism to achieve these goals is the addition of a vertical secondary unit to the rear of the house to negotiate access, light, and code requirements.
Building and fire codes were less regulated during the time of construction for several of the Edwardian houses in San Francisco. This resulted in an (non-complying) egress only for the second level unit. Not only did this stair create unused space for the tenants of the ground level unit, it also meant that the top unit did not have a secondary egress to the rear yard. This inadvertently URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
TRE
AT S
24
TH
ST
T
THE MICRO-VERTICAL | BIANCA KOCH
NUMBER OF ROOMS
light access open
light access 30’
open
122’
light access open
light access open light access open
Like many San Francisco houses, when the original Edwardian type was densified for more inhabitants, a small addition was created on the rear of the house to add a second set of access stairs. This appendage also provided small amounts of space to each of the respective units; utilized for additional kitchen space, storage/ laundry, and a den. The proposed
INTENDED USE 1904
MODIFIED USE 2015
second floor
second floor
first floor
first floor
garage
garage
78 lf built
93 lf built
97 lf built
92 lf built
98 lf built
secondary unit re-appropriates the footprint of this addition to stay within the existing envelope of the building. Designed as a vertical unit, the design employs a circulation stair to organize the program — creating storage, shelves, desks, and sleeping platforms. A new code-complying stair is introduced on the exterior to link into the three existing units
as well as proposed secondary unit. This unit challenges the notion of what we often consider unusable space, to rethink how the vertical circulation itself can be the impetus for reconsidering micro-domesticity through a vertical field condition of curated platforms.
30
’
2’
12
2’
12
’
HOUSE AND YARDS
1904
30
LOT WIDTH
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
EGRESS STAIR SUN DECK
STUDY SLEEPING PLATFORM
DINING / LIVING
06 07
BACKYARD PATIO
PRIVATE ENTRANCE
THE MICRO-VERTICAL | BIANCA KOCH
08 09
POROSITY FROM ABOVE Type: Victorian Neighborhood: Pacific Heights Location: Pacific Avenue and Octavia St. Average Studio Rental Price: $2,259 Block Size: 223 ft x 313 ft Number of Lots: 21 Lot Size: 40’8” x 128’2’’ Typical Parcel Size: 26 ft x 111.5 ft Zoning Height: 55 ft Also found in: those neigborhoods with extreme upslope lots Historic Sq ft: 4,810 Present Sq Ft: 4,810 Proposed Sq Ft: 5,450 ADU Sq Ft: 640
08
22
3'
x3
13
11
'
5
va ra
80 v ara
BLOCK
11
1.
5'
x5
2'
N
11
1.
5' x
26
'
LOT
PARCEL
OPEN SPACE
55'
HEIGHT
Pacific Heights was first developed in the 1870s by organizing a series of Victorian homes along an east-west ridge of San Francisco. An array of strategies have been employed to reconcile the topographic shifts in the neighborhood and the continuity of the city grid, to provide access and light to these houses. This case study examines a large (4,800 sf) Victorian house built on an upslope lot. Due to the sharp grade changes, the house was set back and elevated to be level with the rear yard. Situated a full storey above the front of the parcel, a front garage and stair access was utilized to negotiate this grade change. The garage’s roof has been opportunistically appropriated for an outdoor, publically facing terrace in most cases. The need to reconcile the grade differential inadvertently produced generous ceiling heights within the garage, positioning this space as an ideal location for a secondary unit.
terraces and direct access for the original owners. While the secondary unit has difficulty opening up for light along the trafficked Pacific Avenue, it organizes its light from above and through screens. Accordingly, the secondary unit’s terrace is designed with a gabled roof that affords natural light while creating a sloped seating space. Further to this, the unit is recessed behind a planted screen to create a semi-outdoor solarium— protected from the street, yet still receiving natural light. Within the interior, the natural light that penetrates the volume dictates the location of service and public spaces.
The proposed secondary unit expands on the original garage space to create a large one-bedroom apartment. By shifting the exterior entry stairs, and providing a new, smaller garage, the topographic re-negotiation forms two URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
. AV E C FI PA CI
A VI TA OC . ST POROSITY FROM ABOVE | KELVIN THENGONO
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS
INTENDED USE 1904
light access open
41’
light access
128’
open
light access open
30’
light access
128’
open
light access open
built
MODIFIED USE 2015
131 lf
third floor
third floor
second floor
second floor
first floor
first floor
garage
garage
78 lf built
93 lf built
97 lf built
92 lf built
41’
8’ 12 1904 and 2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
SUN DECK PRIVATE ENTRY PLANTER SCREEN
POROSITY FROM ABOVE | KELVIN THENGONO
07 08
09 10
The Common Light Type: Sunset Neighborhood: Bernal Heights Location: Winfield st. and Esmeralda ave. Average studio Rental Price: $2,498 Block Size: 160ft x 800ft Number of Lots: 20 Lot Size: 25ft x 60ft Typical Parcel Size: 26ft x 70ft Zoning Height: 30ft Also found in: Sunset District Historic Sq ft: 920 sqft Present Sq ft: 1010 sqft Proposed Sq ft: 1490 sqft ADU Sq ft: 570 sqft
27 var a
16
0'
x
80
0'
29
3
va ra
09
BLOCK
70
’x
78
’
N
70
’x
26 ’
LOT
PARCEL
OPEN SPACE
HEIGHT
The Bernal Heights neighborhood remained undeveloped until the 1906 San Francisco earthquake. Soon thereafter, the hilltop was colonized for worker’s homes during the rapid rebuilding of the city. The neighborhood is characterized by a unique Sunset Style typology, which consolidates a series of rooms around a central access point. Referred to as the Sunset Three, Four, or Five, depending on the number of rooms, the house is able to efficiently pack rooms into its plan despite the modest lot size (typically 25’x70’). Several of these units are on a down-sloped lot, which projects the second-storey into the rear yard. The level on grade is typically pulled back because of the down-slope and used for parking or storage. At the same time, the downslope provides access to natural light on the rear of the grade-level and accordingly has often been reappropriated for an extra bedroom that is recouped from storage spaces.
while also maintaining parking for one car. The design revolves around the insertion of a light well that penetrates the two units to bring natural light deep within the interior of both plans. With a series of screens, privacy and access is maintained for both units. This design questions how two occupants can live and share light while also occupying their own distinct spaces.
This case study explores the expansion of the garage space into a secondary unit that gains access to natural light from three facades. The one-bedroom unit provides ample space for sleeping, eating, and work,
30' URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
ST . D EL FI IN W ESME
RALD A AVE
THE COMMON LIGHT | JAIYU FU
.
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS
light access open
25’
MODIFIED USE 2015
97 lf built
70’ light access open
first floor
first floor
garage
garage
97 lf built
100’
light access
111 lf built
25 ’
open
25 ’
25’
INTENDED USE 1950
70’
70’
1950
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
YARD ACCESS PRIVATE SPACE
LIGHT WELL STUDY
08 09
UNIT ENTRY
STREET ENTRY
THE COMMON LIGHT | JAIYU FU
10 The Side Court Type: Free Standing Garage Neighborhood: Mission Location: 22nd & Folsom Average Studio Rental Price: $2,000 Block Size: 240 ft x 520 ft Number of Lots: 10 Lot Size: 120’ x 104’ Typical Parcel Size: 25 ft x 120 ft Zoning Height: 40 ft Also found in: Mission Dolores, Lower Haight, Duboce Triangle ADU Sq Ft: 518 sqft
var a
24
0'
x
52
0'
19
0
va ra
88
10
12 0'
x
10
4'
BLOCK
25 '
x
12 0'
LOT
PARCEL
OPEN SPACE
HEIGHT 40'
N While thought to be a rare entity within the city, the freestanding garage adjacent to a housing unit is found in large quantities in neighborhoods such as the Mission District. These typologies naturally situate themselves on corner parcels, which allow for vehicular entry from an adjacent street. This condition enables the primary residence to obtain natural light along the linear length of the parcel as opposed to the rear yard. By reoccupying the freestanding garage for a secondary unit, this separation of natural light facilitates the design of a highly private apartment that can take advantage of the existing side court.
and living areas are organized through open concept planning. Both the private and public spaces of the unit turn away from the street and embrace the side court. This once industrial storage lot is reconceived as a garden courtyard. The secondary unit is organized to open up to the courtyard, extending its perceptual scale and access to light. Conversely, along the street, a monolithic wood clad façade protects the apartment from the surrounding traffic. This cross-axial organization of publicprivate spaces produces a gradient of programmatic intimacy that results in an inward oriented unit — a needed moment of repose within the urbanity of the city.
The design for the secondary unit capitalizes on the existing structure as a formwork for organizing the apartment’s spaces. A service core comprised of a kitchen and washroom is situated in the center of the unit. This alleviates the need for additional partitions, while acting as an armature for built-in furniture, storage, and closet spaces. To one side, an elevated sleeping area creates spatial intimacy as well as storage spaces below. Opposite the core, public spaces such as dining URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
ST . AT TR E 22N
DS
T.
THE SIDE COURT | ENRIQUE JUSTICIA
LOT WIDTH
HOUSE AND YARDS
NUMBER OF ROOMS
INTENDED USE 1904
light access
25’
205 lf built
open
100’
light access 47’
MODIFIED USE 2015
built
open
186 lf
second floor
second floor
first floor
first floor
73’ light access
garage
light access open
188 lf
built
open
built
garage
167 lf
73’
73’ ’ 47
’ 47 1904
2015
URBANISM FROM WITHIN: A TYPOLOGICAL SURVEY
09 10
PRIVATE ENTRANCE KITCHEN BACKYARD PATIO GROUND LEVEL COMMERCIAL
THE SIDE COURT | ENRIQUE JUSTICIA
SLEEPING AREA
AFTERWORD An Accessory Dwelling Unit (ADU) is a residential unit added to an existing building. ADUs are subordinate to the primary residential unit(s), generally due to their location on the lot and/or the size of the unit. Also known as Secondary Units, In-Law Units, or Granny Flats, ADUs are generally developed using underutilized spaces within a lot, whether a garage, storage, rear yard, or an attic. ADUs are independent units that have their own kitchens, bathrooms and living area. These units can be developed either within the existing building, within an extension to the existing building, or as a separate structure. ADUs are more likely to utilize side entrances, exhibit lower ceiling heights, and experience lower natural light exposure. ADUs can play a unique and important role in a neighborhood’s housing supply by providing an affordable and flexible housing supply. They can have lower constructions costs by utilizing existing infrastructure (such as walls, floors, roofs, and other elements) of the primary structure. Also, they require less materials due to their size. ADUs can help homeowners offset teh costs of their homes, provide more affordable units for renters, and/or allow families to care and support for each other while maintaining independence. With a small investment, property owners can add an ADU. Generated rental revenues can help contribute to mortgage costs. Also in some cases, the addition of an ADU can be completed in concert with seismic sustainability work and rental revenues can offset those costs. Renters can also benefit from ADUs. Generally smaller, subordinate units rent at lower prices than larger units in the same neighborhood. This means ADUs can provide more affordable housing in San Francisco’s neighborhoods, without public funds or subsidies. ADUs can enable families to support each other across generations while maintaining independent
households, or allow people to agein-place. Among the many possible scenarios, an ADU could be occupied by a homeowner’s adult children who may need support while starting their schooling or careers. In other cases, families might like to provide space and care for elder relatives, and could add an accessible ground floor unit to their home. Seniors wishing to age in place may elect to vacate the primary unit but remain in their home by moving to the ADU. In these scenarios, families can reduce their housing costs, while increasing their ability to provide care for each other. ADUs are not a new housing solution; in fact there are many ADUs in San Francisco’s existing housing supply. In some neighborhoods, the original houses from the 1800s were built away from the street and new larger buildings were built in front, turning the original dwelling into a backyard dwelling. In many other places garages or ground floor storage rooms were long ago turned into a separate apartment. SAN FRANCISCO AND ADUS San Francisco, like much of urban America, has an ever changing demand for housing supply, and has often relied on creative and flexible housing types including ADUs to meet the needs of residents, families, and workers. While there is no existing data on the number of ADUs in the City, they are generally considered to be a small but significant portion of the City’s housing supply. Over time, San Francisco’s policies around ADUs have evolved in response to housing trends and community input. Currently some districts in San Francisco allow property owners to add an ADU. More recently the City has expanded the ability of some property owners to add or legalize ADUs. Generally, the benefits of ADUs to a city’s housing supply and for individual property owners is well understood. Further exploration of San Francisco’s building stock and neighborhood fabric, enables decision makers to better understand the potential and limitation of ADUs to contribute to San Francisco’s housing supply.
As San Francisco’s population continues to grow, the city is committed to exploring creative solutions to meet housing needs. Affordability and flexibility remain key themes in housing policy discussions. ADUs can provide flexibility for families over generations, offset the costs of homeownership, and/or provide more affordable housing option for some households. A healthy housing stock has a variety of housing types – to better serve a diversity of needs. As the city explores solutions to address the growing housing needs, we will continue to explore how ADUs might work in our existing housing supply. - Kearstin Dischinger San Francisco Planning
URBANISM FROM WITHIN Editor: Neeraj Bhatia Assistant Editor: Shawn Komlos Cover illustration: Jeffrey Maeshiro with Bella Mang Graphic Designer: Shawn Komlos with Jeff Maeshiro © 2015 California College of the Arts, Division of Architecture, The Urban Works Agency, San Francisco Planning Department, and OpenScope Studio All rights reserved. No part of this book may be reproduced in any form or by any electronic or mechanical means without permission in writing from the publisher. For more information about The Urban Works Agency at CCA University, please visit our homepage at: http://urbanworks.cca.edu Typeface: DIN Pro Printed by: Folger Graphics Printed in: Hayward, CA
URBANISM FROM WITHIN ORGANIZER AND RESEARCH LEAD California College of the Arts-The Urban Works Agency Neeraj Bhatia & Christopher Roach urbanworks.cca.edu PRACTICE AND CODE LEAD OpenScope Studio Principals Ian Dunn and Mark Hogan
EXHIBITION HOST SPUR Noah Christman EXHIBITION CURATOR Neeraj Bhatia EXHIBITION CATALOGUE: Neeraj Bhatia, Editor Shawn Komlos, Assistant Editor and Graphic Design Jeff Maeshiro, Graphic Design Graphic Assistance: Jared Clifton, Bella Mang, Kelvin Thengono, Osma Dossani INSTITUTIONAL FRAMEWORK California College of the Arts Course: Interior Urbanism, Fall 2014 Instructor: Neeraj Bhatia Critic: Christopher Roach STUDENT RESEARCH / DESIGN TEAM: Christopher Baile Evan Bowman Jared Clifton Lisette Devore Jaiyu Fu Tyler JonesPowell Enrique Justicia Bianca Koch Bella Mang Ryan Montgomery Adithi Satish Blake Stevenson Kelvin Thengono EXHIBITION DESIGN AND FABRICATION: Project Leads: Neeraj Bhatia, Christopher Roach, Shawn Komlos, Blake Stevenson, Tyler Jones-Powell Research Drawings: Jeff Maeshiro, Cesar Lopez, Bella Mang Fabrication: Blake Stevenson, Tyler Jones-Powell, Marci Ann EXHIBITION INSTALL TEAM: Noah Christman, Tori Winters, Erin McAuliff, Neeraj Bhatia, Christopher Roach, Jared Clifton, Shawn Komlos, Bianca Koch , Jeff Maeshiro Bella Mang, Tyler Jones-Powell, Blake Stevenson ACKNOWLEDGEMENTS: Jeremy Bamberger, Seth Boor, Amy Campos, Karen Chapple, Melanie Corn, Nataly Gattegno, Jonathan Massey, Randolph Ruiz, Jen Sikora, Ronald Tom, Scott Wiener, Cindy Wu SUPPORTED BY: San Francisco Planning Department SPUR The Urban Works Agency California College of the Arts, Curriculum Development Grant
NIHTIW MORF MSINABRU
POLICY AND PLANNING LEAD San Francisco Planning Department Kearstin Dischinger Kimia Haddadan