Bay Area region / California
Palo Alto ADU rules
& permit guide.
Palo Alto's ADU guide distinguishes state standards from additional city options. Start by checking zoning, the type of ADU and transit proximity. The city's 2025 guide is useful for the design process; use current state guidance for changes that took effect in 2026.
Editorial review 2026-09-07 · View sources
The local detail to check first
Before you choose a design
City options can come with additional city standards. Avoid combining the most generous dimensions from different approval paths.
The municipal guide is the 2025 edition, accessed September 7, 2026. It is not a 2026 ordinance audit. Confirm current requirements with the city.
Local requirements at a glance
Min/max ADU size
Use the city source for the size standard that matches your ADU type and approval path.
Height
Confirm height with the city; building type, approval path and transit location can matter.
Setbacks
Confirm side, rear and front setbacks, plus access and fire requirements, using the city source.
Parking
Confirm the applicable parking exemption with the city. HCD's current handbook explains the state exemptions and replacement-parking rules.
Process
Check the Property Information Map and consult the Planner on Duty about eligibility. Choose detached, attached, conversion or JADU, then use that section of the guide. Confirm current standards and prepare the appropriate building permit checklist. Explore the city-linked ADU Plans Gallery; gallery plans still need site-specific permits.
Your next three steps
- Check the Property Information Map and consult the Planner on Duty about eligibility.
- Choose detached, attached, conversion or JADU, then use that section of the guide.
- Confirm current standards and prepare the appropriate building permit checklist. Explore the city-linked ADU Plans Gallery; gallery plans still need site-specific permits.
2026 state-law context
ADUs and JADUs have different occupancy rules
California generally prohibits local owner-occupancy requirements for ADUs. A narrow exception applies to certain separately sold affordable ADUs. For JADUs, owner occupancy generally applies when the bathroom is shared with the main home; separate-bathroom JADUs are treated differently under 2026 law. Check the HCD handbook and your project's permit conditions.
Older local summaries may not reflect the latest state changes. Read HCD’s March 2026 handbook, pages 32–33.
Questions for your first planning conversation
- Which approval path applies to my building and ADU type?
- Do easements, trees, slope, access or fire conditions affect placement?
- Which utility upgrades and agency reviews should be included in my budget?
- Are preapproved plans available, and what site work still needs review?