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Permit guides
ADU Permits in Belmont: a Homeowner's Guide
Belmont publishes its ADU process as six numbered steps — with stated review clocks at each stage.
Last updated October 2026. Rules change; always confirm current requirements with the city before you build.
Who handles your permit
ADU permits in Belmont run through the Community Development Department via the Belmont Permit Center, using the city's eTRAKiT online portal. Fire sprinkler review falls to the South County Fire Authority. The city's published ADU page lays out the process as six explicit steps — rare clarity for the Peninsula.
What you can build
1,200 sq ftMax for a detached ADU under state law
30 daysPublished initial review clock — a resubmittal restarts another 30 days
21 daysEach round of plan revisions can take up to 21 days to process
One PDFPlans must be submitted as a single PDF document
CovenantOwners sign a covenant limiting the ADU to long-term rentals
4 ftMinimum side and rear setbacks for detached ADUs
The six steps
- Create an eTRAKiT login to track the project through the city's portal.
- Apply and attach plans — all in one PDF. Review can take up to 30 days; if corrections come back, the resubmittal gets another 30-day clock.
- Revisions, if needed — each revised plan round takes up to 21 days once resubmitted.
- Permit issuance — pick up the approved plans through the city's pickup process.
- Sign the Covenant Agreement — required before construction, stating the ADU will be used for long-term rentals only.
- Construction and inspections — build to the approved plans; field changes need prior approval.
The covenant matters for investors. Belmont requires owners to sign a recorded covenant restricting the ADU to long-term rental use. If your plan involved short-term rental income, know this before you spend on design.
What goes into the submittal
- Geotechnical and engineering geology reports, plus grading and drainage plans — Belmont's hills make these standard, not exceptional
- Fire sprinkler plan per NFPA 13-D, prepared by a licensed fire sprinkler contractor or fire protection engineer
- Driveway plan and profile with grades and cross slopes; development summary table (floor area, slope %, setbacks) on the first sheet
- Construction management plan for substantial work: schedule, haul routes, staging areas, neighbor notice, erosion control
- Arborist report identifying the condition and disposition of all trees on site
Where applications usually get stuck
- Revision cycles. At up to 21 days per round, two or three correction cycles can add months — complete first submittals pay off here more than anywhere.
- Geotechnical review. Hillside lots can trigger peer review of the soils investigation on top of the report itself.
- The covenant surprise. Owners who learn about the long-term-rental restriction late sometimes redesign the project's economics mid-stream.
Not sure where to start? That's the part we do. We check your property against the requirements, coordinate the plans and specialists, and manage the submittal and corrections — one point of contact.