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South San Francisco · Building on your lot

Sheds, garages and other accessory structures in South San Francisco

South San Francisco limits all accessory buildings together to 20% of the main building's footprint or 220 square feet, whichever is greater.

Key points

  • Accessory buildings: South San Francisco limits all accessory buildings together to 20% of the main building's footprint or 220 square feet, whichever is greater.

Each rule below links to the section of the South San Francisco Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What South San Francisco's code says

South San Francisco code What South San Francisco's code adds
Size or lot coverage
  • At most 20% of the main building's footprint or 220 square feet, whichever is greater.
    Applies: Combined footprint of all accessory buildings.
    § 20.300.002 · code text
    The combined footprint area of all accessory buildings may not exceed 20 percent of the footprint of the main building or 220 square feet, whichever is greater.
Side and rear setback
  • At least 5 feet, except as the code provides.
    § 20.300.002 · code text
    The minimum setback for accessory structures is five feet except as provided below:
  • Can sit right on the interior side or rear lot line (0 feet).
    Applies: Detached structures under 220 square feet, if no roof water drains onto the neighbor and Building Code rules are met.
    § 20.300.002 · code text
    Except as provided above, detached accessory structures less than 220 square feet in size may be located on an interior side or rear lot line, provided that the building or structure is constructed so that no water drains from the roof onto an adjacent property, and all Building Code requirements are met.
Distance from the house
  • At least 6 feet from the main building, including the roof.
    § 20.300.002 · code text
    No detached accessory building shall be located closer than six feet from the main building, inclusive of roof covering.

Who this affects

HomeownersContractorsDesigners

Frequently asked questions

How big can a shed or accessory building be in South San Francisco?

South San Francisco limits all accessory buildings together to 20% of the main building's footprint or 220 square feet, whichever is greater.

General information, not legal advice.

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Ask GoCodebook how South San Francisco's sheds, garages and other accessory structures rules apply to your situation and get an answer that cites the section.

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