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Residential Expansion Threshold

December 5, 2017 - The Planning Department regrets to announce that it has suspended efforts to advance the proposed Residential Expansion Threshold (RET) Project to allow for additional review.

The Residential Expansion Threshold Project's primary objective is to eliminate the ineffective Tantamount to Demolition controls and place more emphasis on the size and density of buildings by incentivizing a higher number of residential units while discouraging exceedingly large single-family homes. However, the Department believes it is necessary to shift its approach, and instead work in collaboration with the Department of Building Inspection (DBI) to improve the City's considerably complex definition of "demolition."

The Department believes in a comprehensive and sensible approach to guiding development in the City's residential districts. We will update the Planning Commission and other key stakeholders in the coming months as further details are determined.

In 2005, the Planning Department began to look at project applications that weren't proposing to demolish entire residential properties, but were proposing to remove a significant portion of the building. As they were not classified as "demolitions" as defined by the Department of Building Inspection (DBI), these projects were not subject to Planning Commission review.

To address this, legislation was finalized in 2007 to create regulations on demolitions of existing housing and what is currently known as Tantamount to Demolition. As a result, any project application that is considered Tantamount to Demolition is reviewed no differently than a formal demolition project and will typically receive additional scrutiny from the Planning Commission.  

What is "Tantamount to Demolition"?

Any project application that proposes one or more of the following criteria is considered "Tantamount to Demolition" and subject to San Francisco Planning Code Section 317.

  • A major alteration of a residential building, removing more than 50 percent of the front and rear façade (combined); and
  • Removing more than 65 percent of all exterior walls, or
  • A major alteration of a residential building removing more than 50 percent of the Vertical Envelope Elements (defined as all exterior walls that provide weather and thermal barriers between the interior and exterior of the building, or that provide structural support to other elements of the building envelope); and
  • More than 50 percent of the Horizontal Elements (defined as all roof areas and all floor plates, except floor plates at or below grade) of the existing building, as measured in gross square feet of actual surface area

However, we have found that the current controls have led to project sponsors designing just short of the threshold, resulting in inferior design and/or significantly expanded projects. The current controls have led to project sponsors designing just short of the threshold, with these results:

  • Allowing major additions. A project can significantly expand the size of the existing housing while still meeting the Tantamount to Demolition threshold, thus be approved administratively (no Commission hearing required).
  • Potential for inferior design.

The Department agrees with the public that Tantamount to Demolition is not effective in respecting neighborhood character. 

Eliminating Tantamount to Demolition

In keeping with the ongoing effort of changing practices to better meet the needs of the City, the Department is proposing to remove the Tantamount to Demolition calculations from the Planning Code and replace them with a Residential Expansion Threshold, or a standard that would limit the size of the finished project to be more consistent with neighborhood character. The Department believes that limiting the overall size of a single family home can ultimately help balance the character of the neighborhood with a property owner's rights to improve and expand their property. This new standard will provide clarity for both project sponsors and their neighbors and will streamline the overall process; effectively saving time for both sponsors and staff.

The intention behind Section 317 is to address the ongoing shortage of affordable housing.  The Department recognizes projects that are currently designing to the Tantamount to Demolition thresholds are not more affordable, and as such the Department is proposing to separate the policy issue of large alterations from the preservation of existing housing.  As part of this effort, projects that would be subject to this new threshold would be reviewed in a new code section. These proposed changes do not affect any policies related to the review of mergers or proposed demolitions of any units under rent control.

Current Proposal

The Department previously considered requiring Planning Commission review for projects that result in a unit that is more than 3,000 GSF.

After receiving feedback at community meetings and presentations to the Planning Commission on the proposed standards, the Department decided to re-evaluate its approach. We're now considering thresholds for RH-1(D), RH-1, RH-2, and RH-3 Zoning Districts that would determine when a project can proceed with a staff-level approval vs. when a project requires approval by the Planning Commission.


  • August 31, 2016: First informal meeting with community members
  • September 22, 2016:  Informational presentation to the Planning Commission
  • September – October, 2016: Community Conversation on Proposed Changes October 12, 6-8pm at Planning Department, 1650 Mission Street, Room 431
  • October 4, 2016: Meeting with architects (open to the public) Noon-1pm at Planning Department
  • October 12, 2016: Community Meeting, 6:00 - 8:00 p.m. at Planning Department 
  • October 27, 2016: Informational presentation and update to the Planning Commission
  • May 2017: Community Conversation on Updated Proposal at Planning Department
  • June 1, 2017: Informational presentation and update to the Planning Commission
  • August 15, 2017: Community Conversation and Presentation to Coalition for San Francisco Neighborhoods
  • September 6, 2017: Roundtable with Community and Neighborhood Stakeholders
  • September 11, 2017: Roundtable with Design and Development Stakeholders
  • September 12, 2017: Roundtable with Housing Advocates
  • October 2, 2017: Community Conversation & Presentation with Planning Association for the Richmond (PAR)
  • October 10, 2017: Community Conversation & Presentation with Neighbors and Community Members within Districts 1, 2, 4, 5, 7, 8
  • October 16, 2017: Community Conversation & Presentation with Neighbors and Community Members within Districts 3, 6, 9, 10, 11
  • Ocober 24, 2017: Community Conversation & Presentation at YIMBY