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San Francisco activates online portal to streamline ADU development and help combat housing crisis

City and County San Francisco

San Francisco, CA

Symbium's Build portal enables City planners, design professionals, developers, and homeowners in San Francisco to understand whether an Accessory Dwelling Unit (ADU), also known as secondary dwelling and in-law units, is allowed on a particular parcel, what development standards apply, and the ensuing processes.

Topics Covered

Housing & Affordable Housing
Process Improvement


Initial: 20 Thousand USD


General Fund/Existing Public Funds

Public Private Partnership

State and local grants

Project Status

Operational since 2019

Gov Champion

SF Planning Department

Problem Addressed

San Francisco is facing a housing crisis, with far fewer units available and under construction to meet its housing needs.

As far back as 2014, the City of San Francisco began to encourage ADU production as a way to create more housing. Their ADU Program, which has expanded to allow ADUs citywide in zoning districts that allow residential use, provides relief from certain Planning code requirements and offers streamlined review. As of June 2020, San Francisco has approved 1,300 ADUs and would like to see even more built - while recognizing the hardships of doing so during the COVID-19 pandemic.

Yet even with an ADU Program to streamline review, challenges remained for the Planning Department in supporting homeowners interested in building them. The current process for determining whether an ADU can be built on a property is often laborious and time-consuming, requiring a manual review of state and local regulations. This can result in homeowners making multiple telephone calls and in-person visits to the planning counter. On average, these inquiries take longer for staff to process given the relative inexperience of homeowners and the complex and fast-changing regulations. Challenges like this are compounded in cities like San Francisco where ADU approvals are dependent on homeowner compliance with ever-changing rules and regulations from multiple departments.

Solutions Used

To improve the ADU approval and development process for residents and City staff, San Francisco launched a homeowner-friendly, web-based portal with Symbium.

Symbium Build is an intuitive yet powerful web-based tool that empowers homeowners, design professionals, and City staff to:

1. Easily visualize where ADUs are allowed;

2. Understand the applicable, site-specific development standards; and

3. Understand the ensuing processes, including permits and fees, to build an ADU on any particular parcel.

Symbium Build is even more relevant during the COVID-19 pandemic where planning counters around the country have gone virtual, allowing homeowners to do their feasibility research from home.

Symbium's Build portal for San Francisco and other jurisdictions is available to the public at https://build.symbium.com



Saves staff time - Homeowners and applicants can avoid time consuming phone calls and in-person appointments; instead, they can find answers online in an easily understood format.


Saves staff time - Users can download information about their intended ADU project in a user friendly and customizable format, which streamlines questions at the planning counter.


Increase in the quality of ADU applications -Partnering with Symbium on the Build portal was one of the City’s many process improvements and updates to external information.


More accessible and user friendly - the portal interprets complicated requirements into a user-friendly format, both written and graphic, allowing users to customize and visualize their ADU

Something Unique

Initially launched to streamline the ADU process for cities, Symbium also supports commercial business zoning so anyone can instantly visualize where a specific business type is allowed (i.e. where in San Francisco a 2nd floor chain cafe is permitted). Learn more at https://symbium.com/buildbusiness.

Who Should Consider

Cities and counties that would like to increase housing supply through Accessory Dwelling Units, save staff time, increase the quality of applications, and improve citizen engagement should consider Symbium.

Last Updated

Mar 20th, 2021

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