§ 207.2.


(a) Second units, as defined and referred to in Government Code Section 65852.2, are precluded in RH-1(D) and RH-1 zoned areas, except where second units are currently permitted under Section 209.1(m) or (n) for units designed for and occupied by senior citizens and except as may hereafter be permitted by later amendments to this Code governing second units.

(b) Government Code Section 65852.2 requires a City to adopt either an ordinance permitting or precluding second units within single-family and multifamily zoned areas or, in the alternative, to be subject to certain restrictions set forth in Government Code Section 65852.2(b). The provisions of this ordinance, in light of other provisions of the Planning Code governing second units, do not result in the total preclusion of second units within single-family and multifamily zoned areas and therefore San Francisco has a legislative scheme which complies with Government Code Section 65852.2(a). In the event that it is determined, however, that San Francisco’s legislative scheme does not comply with Government Code Section 65852.2(a), the following findings are made with the intent of complying with Government Code Section 65852.2(c).


San Francisco’s total land area is approximately 49 square miles and much of this land is not open to development because of topography or public ownership. San Francisco does not have the option open to many other cities of annexing undeveloped land currently outside its borders.


San Francisco already has higher density development than other cities in California, both in terms of units per square feet of lot area and in terms of units per linear feet of street frontage. The density for housing development in San Francisco ranges from 4,000 square feet of lot area per unit in RH-1(D) (House, One-Family Detached Dwellings) Districts to 200 square feet per unit in RM-4 (Mixed Residential, High Density) Districts. Except for districts which require a lot width of 33 feet and an area of 4,000 square feet, the minimum lot size for housing development is 2,500 square feet in area, following the standard lot size in San Francisco (25 X 100 square feet), or 1,750 square feet for lots within 125 feet of a corner. This density and lot size requirement allows greater density than other jurisdictions in California where the typical density and lot size is about 5,000 square feet per unit for single-family dwellings and 1,500 square feet per unit for multifamily development.


San Francisco is the most densely populated city in California. It is the fourth most densely populated city in the nation following only New York City and two cities in New Jersey (Jersey City and Patterson).


The limited land area and the limited developable land area of San Francisco make it difficult to provide sites to replace single-family houses lost through conversion to a higher density. Once single-family homes are converted into multiple dwelling structures by the addition of a second unit, single-family housing stock is eliminated from the existing supply of single-family homes. The irrevocable loss of the limited supply of single-family housing stock throughout the City will adversely affect the health, safety and welfare of San Francisco residents.


Single-family residences have in recent years been demolished at a faster rate than any other residential structures in the City primarily because new multiple-unit residential development in the City often occurs as the result of the demolition of single-family homes in multiple-unit districts. Single-family homes were 37 percent of the residential units demolished in 1984, and 61 percent of the residential units demolished in 1983. Single-family homes represented an even larger percentage of the residential structures demolished. Single-family homes were 86 percent of the residential structures demolished in 1984, and 74.4 percent of the residential structures demolished in 1983.


Single-family structures represent only 1/3 of all residential structures in San Francisco compared to 60 percent of the residential structures in the State of California. Single-family homes accounted for 18 percent of the new housing units in San Francisco in 1984, and 7 percent of the new units in 1983. Other jurisdictions in California had single-family structures representing approximately 50 percent of their new residential building permits for the same period.


The number of families in San Francisco declined in the years from 1970 to 1980, as evidenced by the school enrollment for the population group under 15 years old. The decline in enrollment was from 106,900 to 83,790. The zoning policy of the City and County of San Francisco should encourage families to live in the City rather than encouraging them to leave the City. A further decline in the number of families living in the City is detrimental to the public health, safety and welfare.


The addition of second units to single-family dwellings usually results in an increase in the cost of those dwellings, and, in addition, to the cost of the remaining smaller supply of single-family homes without second units. An increase in the cost of these types of dwellings will discourage families from living in the City because the cost of dwellings most suitable for families will be beyond the means of many who would otherwise live in the City.


San Francisco will probably face a need for more large units in the future than it did in the past, as the population ages and the new baby boom continues. Many women born between 1945 and 1952 who delayed child-bearing during the 1970′s are now having babies at the same rate as women born after 1952.


The addition of second units in single-family houses throughout the City will irrevocably deplete its limited supply of single-family homes and discourage families from living in the City by removing the type and size of dwelling units most suitable for families. Many of the residential parcels in the City are less than 2,500 square feet in size or 1,750 square feet for corner lots and do not meet minimum lot size standards. Many of these parcels were developed without required garages or with minimal garage space, and do not comply with existing off-street parking requirements. The addition of second residential units in these areas could only worsen existing congestion.


Parking problems are severe in a number of areas of the City because of its dense population. The addition of second units in such areas will exacerbate the parking problem. Imposing off-street parking requirements on secondary units would only partially alleviate that problem in that additional units cause increased traffic other than that engaged in by the occupants of the units (such as persons visiting the occupants for social or business purposes) as well as by the occupants of the units.


Increased parking problems in areas of the City already burdened with traffic congestion adversely affects the health, safety and welfare of the residents of such areas by interfering with access to off-street parking spaces, requiring additional police services to control traffic problems and unlawful parking, requiring occupants and visitors to park further from their homes (thereby also exposing themselves to greater inconvenience and, in some instances, threat to safety), and interfering with access by emergency vehicles during an emergency (a problem which is further complicated in areas with narrow streets, winding roads, and other topographical features which make access by vehicles difficult).


A need exists in San Francisco for additional affordable housing. Allowing second units in RH-1(D) and RH-1 Districts is one means of providing such housing. However, to allow second units without restriction in all areas currently zoned RH-1(D) and RH-1 would adversely affect the health, safety and welfare of the public by permitting the conversion of an undue number of single-family houses to multi-family units; by eliminating low-density residential areas in the City and thereby depriving those who desire to live in the City without the stress of living in higher-density areas of their opportunity to do so; and by permitting second units to be added in areas where undue traffic congestion and the attendant difficulties described above, will occur.


A further period of time is needed in order to determine those areas of the City where the traffic congestion problems described above would be least likely to occur and where second units may therefore be permitted without adverse impact to the public.


There are no large districts suitable for the provision of second units, but instead there are small subareas which must be reviewed on a case-by-case basis with community participation in the review process. A case-by-case review is needed in order to determine those areas of the City where the traffic congestion problems described above would be least likely to occur and where second units may therefore be permitted without adverse impact to the public. Furthermore:

(A) The Planning Code presently permits a secondary unit in all single-family homes in RH-1(S) (House, One-Family with Minor Second Unit), RH-2 (House, Two-Family) and RH-3 (House, Three-Family) Districts no matter what the lot size. Second units in single-family homes are permitted in all other multifamily residential districts (all RM and RC Districts), depending on the size of the lot.

(B) The Planning Code Section 209.1(c) permits the mapping of the RH-1(S) (House, One-Family with Minor Second Unit) District. These RH-1(S) Zoning Districts provide for a two-family dwelling with the second dwelling limited to 600 square feet of net floor area. The second unit remains subordinate to the owner’s unit and the structures retain the appearance of single-family dwellings. The RH-1(S) Zoning District has been mapped in four areas of the City. Additional mapping of the RH-1(S) Zoning District may be used to legalize existing secondary units in single-family homes and to increase the number of secondary units.

(C) Dwellings specifically designed for and occupied by senior citizens are presently permitted at a density ratio or number of dwelling units not exceeding twice the number of dwelling units otherwise permitted as a principal use in the district by the City Planning Code (Section 209.1(m) and (n)).

(16) Restricting second units in single-family homes in San Francisco’s RH-1(D) and RH-1 Zoning Districts may limit the housing opportunities of the region. However, over time, applications for RH-1(S) zoning designation may be reviewed on a case-by-case basis by the Planning Commission and its staff, the Board of Supervisors and the Mayor and where second units would be appropriate and would not adversely affect the public health, safety and welfare of residents of the City and County of San Francisco, such rezoning applications would be approved. Neither the provisions of this Section nor those of Government Code Section 65852.2 preclude the City from hereafter amending this Code in order to permit second units in additional situations designed to address specific housing needs and circumstances unique to San Francisco.


San Francisco has been and will continue to be a major provider of affordable housing opportunities in the region.


Currently (1986) San Francisco administers 6,766 units of public housing and 2,574 Section 8 certificates.


Article 34, Section 1 of the California Constitution requires the approval of the electorate as a condition to the development or acquisition of a low-rent housing project by the local jurisdiction. San Francisco has met the requirement with the City’s voters approving the development of a maximum of 3,000 low-income housing units by a vote on Proposition Q on November 2, 1976. Together with the units previously approved, approximately 4,000 low-income housing units may be developed, constructed or acquired.


Between 1981 and 1985, San Francisco’s housing production efforts included, but were not limited to the following:

1. San Francisco undertook a major rezoning of underutilized land which will allow the development of 14,000 housing units. Another 1,700 units are underway on vacant publicly owned sites in the City.

2. San Francisco set aside $10,000,000 in general-fund monies for an Affordable Housing Fund. $6,100,000 of this amount is committed to create 443 housing units including the renovation of 82 vacant public housing units into privately managed two- and three-bedroom apartments.

3. San Francisco combined $1,000,000 in federal Community Development Funds with the proceeds of an $8,000,000 bond issue to finance home improvement loans for low- and moderate-income homeowners.

4. The Office Housing Production Program (OHPP), under which high-rise office developers are required to build or contribute to housing on a formula based on the size of their projects was instituted in 1981. The program has resulted in $25,000,000 and over 3,700 housing units to date.

5. The City of San Francisco has sold $84,000,000 in two bond issues since 1982 to provide 30-year, 10¾ percent mortgages to some 900 low-to middle-income first-time homebuyers. In addition a $42,000,000 bond issue was sold to finance up to 400 homes with 9.8 percent mortgages. In June, 1985 the City sold $44,000,000 in mortgage revenue bonds to finance the construction of 563 units of rental housing on five sites.


Between 1980 and mid-1985 community-based nonprofit organizations which receive Community Development Block Grant funding built 1,166 new housing units for low- and moderate-income households. At the time of the 1985 report on their activities they had 200 units under construction, and 426 units planned. During this same time the organizations rehabilitated 1,780 units for lower-income households, had 426 units undergoing rehabilitation, and had plans to rehabilitate 1,285 units.



(Added by Ord. 155-84, App. 4/11/84; amended by Ord. 526-85, App. 11/27/85; Ord. 324-86, App. 8/8/86; Ord. 140-11, File No. 110482, App. 7/5/2011, Eff. 8/4/2011)

Divisions (a), (b), (b)(15)(A), (b)(15)(B), (b)(15)(C), and (b)(16) amended; Ord. 140-11, Eff. 8/4/2011.


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