Title
Report to discuss options to allow moderate density housing in residential districts that currently only allow single family dwellings. (Lisa Costa Sanders, Project Administrator and Billy Gross, Senior Planner)
label
RECOMMENDATION
Recommendation
Staff recommends that the City Council provide direction on an option to modify single family zoning to allow more housing with the General Plan update.
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BACKGROUND/DISCUSSION
During the General Plan Update process to date, the City’s approach has focused on developing new housing in areas near transit and jobs, while preserving existing residential neighborhoods that traditionally have been characterized by single-family homes.
Meanwhile, however, there has been a national policy discussion to address “missing middle” housing with approaches that allow moderate density housing in areas zoned solely for single family homes. Missing middle housing as a term typically refers to housing types including duplex, triplex, fourplex, cottage, townhouse and other smaller multi-unit attached and detached housing types (“multi-plexes”) compatible in scale with single family homes. These housing types generally have small- to medium-sized footprints and are often two stories or less, allowing them to blend into existing neighborhoods. Missing middle housing also refers to housing that is affordable to those earning between 80-120% of the area median income, which is too much to qualify for subsidized housing and too little to afford to purchase high-income properties or rent at market rates.
These moderate-density housing types were commonly built in neighborhoods prior to the 1940s (thus the term “missing middle”). After this time period, the adoption of zoning ordinances that separated residential use types resulted in large areas where only single-family dwellings were allowed to be built. South San Francisco is in keeping with this general profile. The broader downtown area has many existing examples of moderate-density housing, particularly along Miller, Grand, Baden and Commercial Aves east of Orange Ave. These buildings were constructed in the early- to mid-1900s, up to the 1960s, and contain four or more units. The majority of these buildings are no more than two stories; example imagery is included in the attached presentation (Attachment 3).
By the early 1950s, the City had adopted zoning districts that restricted residential densities. The 1953 Zoning Ordinance includes a R-1 District allowing only single family dwellings, a R-2 District allowing single family dwellings and duplexes, and a R-3 District allowing multi-family units. Based on this, the subdivisions that were developed between 1940 and 1960 (such as Sunshine Gardens, Buri-Buri, and Brentwood) were entirely single-family detached housing. The allowed residential uses in these districts have remained largely unchanged since that time, with R-1 now called RL Low Density Residential, R-2 now called RM Medium Density Residential, and R-3 now called RH High Density Residential. South San Francisco’s low-density residential zoned areas currently allow one single family residence, and were recently updated to allow an accessory dwelling unit (ADU) and a junior accessory dwelling unit (JADU), in keeping with state law.
South San Francisco’s existing inventory of housing, as shown in the table below, indicates the percentage of all residential units for each specific housing type, as well as the percent of total land area. Single-family residential zoning dominates the land area in the City that is currently devoted to housing. A smaller percentage of units and land area is devoted to moderate-density housing types.
|
Housing Type |
Percent of residential units |
Percent of total City land area |
|
Single family residential |
67% of units |
33.8% of land area |
|
Duplex/triplex/fourplex |
8.1% of units |
1.5% of land area |
|
Multi-family (5+ units) |
23.4% of units |
4.1% of land area |
Missing Middle Housing Policy Examples
Many state and local governments are analyzing options related to housing provision and affordability, including new zoning regulations to allow moderate-density units in areas that previously only allowed single-family units. The intent is that over time, the residential neighborhoods in these communities will have a mix of single-family homes and multi-plexes as properties are developed. Single family homes are still permitted with the new zoning regulations, but they are no longer the only option available.
To ensure compatibility with their surroundings, missing middle housing policies typically include zoning standards and design guidelines or form-based codes to control the outward appearance of buildings to maintain the overall neighborhood scale and character. As an example, the City of Eugene, Oregon prepared a handbook that highlights potential design principles and strategies and identifies prototypes for each of the different housing types (see Attachment 1).
With appropriate design guidelines, multi-plex buildings can be designed to take the form of a single-family home in space and character, but contain multiple smaller units compared to traditional single-family residence. As an example, in South San Francisco’s typical low-density residential zoning districts, single family homes are allowed a maximum floor area ratio of 0.5. On a 5,000 square foot lot, this floor area ratio would allow 2,500 square feet of built area, which would accommodate an approximately 2,300 square foot unit and a one-car garage. If allowed, a duplex could be developed with two 1,050 square foot residential units and a two-car garage, and a triplex with three 630 square foot units and a three-car garage. If moderate-density housing were allowed in single-family neighborhoods, South San Francisco’s current parking regulations would need to be updated, as parking standards for multi-plex buildings typically require one off-street space per unit, where South San Francisco currently requires two-four off-street parking spaces per residence in low-density zoning districts (depending on the number of bedrooms and house size).
Jurisdictions that have adopted modifications to single family zoning to allow multi-plex buildings found support from activists including, affordable housing and tenants’ advocates, environmental organizations, and for-profit and nonprofit housing developers. Opponents to these modifications typically express concern with property rights, degradation of traditional single-family neighborhoods, increased parking and traffic impacts and increased demand for services throughout the community.
Following are recent examples of middle missing housing policies highlighting different approaches:
City of Sacramento
The City of Sacramento is currently updating its General Plan. In January 2021, the Sacramento City Council identified a list of key strategies being considered for their 2040 General Plan. One of these key strategies is to permit a greater array of housing types, such as duplexes, triplexes, and fourplexes in existing residential neighborhoods. The proposed strategy would not eliminate the ability to construct single-family dwellings, but would allow duplexes, triplexes and fourplexes by-right in traditionally single-unit zone neighborhoods. Sacramento is proposing to regulate the form and size of buildings to ensure that the new housing types would not be incompatible to the surrounding area. All housing types would still have to comply with the Citywide Design Guidelines. See Attachment 2 for more information on Sacramento’s proposal.
City of Portland, Oregon
The City of Portland adopted the Residential Infill Project in August 2020, legalizing up to four residential units on residential lots. Portland’s regulations are different in that they allow up to six units when at least half are income restricted to families earning less than 60% of the median family income. Portland’s regulations also differentiate lot coverage allowances for the different housing types; one-unit buildings are allowed to cover 50% of the lot, two-unit buildings are allowed 60%, and triplexes and fourplexes up to 70%.
State of California
In California, recent examples include state legislation related to accessory dwelling units (ADUs) and junior accessory dwelling units (JADUs). As of January 21, 2021, an ADU and JADU are allowed on a lot with an existing single-family dwelling unit in any configuration provided that the JADU is created entirely within the existing single-unit dwelling. The State is currently considering Senate Bill 9 (SB 9), which would allow for duplexes and lot splits in single-family residential zones to be allowed by-right and would streamline the associated process.
General Plan Update Process / Next Steps
Staff and the consultant team are continuing with the General Plan Update process. The last major milestone was the City Council’s acceptance of a Preferred Land Use Scenario (PLUS) in November 2020. Subsequent to this action, the General Plan team has transitioned to the following efforts which would be influenced by the missing middle housing topic:
• Preparing draft General Plan policy frameworks for each of the GP Elements (including Land Use, Equity, and Sustainability).
• Updating the City’s Housing Element concurrently with the General Plan update process. The regional housing needs allocation (RHNA) for the next Housing Element cycle is 3,957 units, which includes 872 very low-income units; 502 low-income units; 720 moderate income units and 1,863 above moderate-income units. Missing middle housing units typically serve moderate to above moderate-income households and could be a tool to meet housing obligations.
• Preparing the Zoning Ordinance Update. One of the new items proposed in the Zoning Ordinance is the inclusion of Form-Based Codes. As discussed above in the examples from other jurisdictions, the use of form-based codes for missing middle housing would better ensure compatibility with surrounding neighborhoods.
At the outset of the General Plan update process, staff and the consultant team focused efforts to prioritize new housing in areas near transit and jobs. Specifically, new housing land use designations are proposed in the El Camino Real, Lindenville and East of 101 sub-areas as part of the accepted Preferred Land Use Scenario. Staff and the consultant team did not study options to allow missing-middle housing types in low-density residential zoning districts based on early feedback. The public was informed at community meetings that no land use changes were contemplated for the single-family districts. If this approach is recommended for further consideration, staff recommends additional community outreach.
It would be possible to incorporate this analysis into the General Plan/Housing Element Update if staff were given such direction in the near timeframe. If the City Council wishes to explore this approach further, staff and the consultant team have prepared a two-phase approach:
1. Phase 1 would include initial technical analysis on missing middle housing in South San Francisco, examples of development regulations from other jurisdictions, and exploration of missing middle scenarios, including anticipated new housing. The project team would facilitate up to two (2) virtual community meetings and a Community Advisory Committee meeting on missing middle housing. Results of the analysis and public engagement would be presented to the City Council for recommendation and initiation of Phase II. Phase I is anticipated to run from April to June and cost $49,600.
2. If initiated by City Council, Phase 2 would include additional Zoning Code analysis and the reissuing of the EIR Notice of Preparation. The Zoning Code would include: micro-scale analysis of the City's Residential Low and Residential Medium areas; the development of additional transect zoning; and the creation of building and frontage types appropriate for these areas. Phase II is anticipated to run from July - August at a cost of $50,400.
The total estimated cost for Phase I and Phase II as outlined above is $100,000 and the work is estimated to extend the overall General Plan update process by up to four months.
Alternatively, the City Council could pause on proceeding with further analysis at this time and continue to track progress of SB 9, which is currently under consideration at the State Legislature. If SB 9 is enacted, staff would bring forward the necessary zoning code revisions for City Council consideration to ensure consistency with State law.
CONCLUSION
Staff recommends the City Council provide direction to staff.
Attachments:
1. City of Eugene, Oregon Missing Middle Housing Handbook
2. City of Sacramento FAQ on Housing Policy Proposal
3. City Council Presentation