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Permit guides

ADU Permits in El Cerrito: a Homeowner's Guide

What you can build, which permits you need, and how the review actually works — in plain language.

Last updated October 2026. Rules change; always confirm current requirements with the city or county before you build.

Who handles your permit

ADU permits in El Cerrito run through the City of El Cerrito's Community Development Department — Building Division, at 10890 San Pablo Avenue, El Cerrito, CA 94530, (510) 215-4360. Applications are submitted as one digital PDF plan set (24"x36" maximum) to the Building Division, with city forms also available through the city's document center. But there's a second reviewer you won't find in most Bay Area cities: the Stege Sanitary District. Every plan set must be reviewed and stamped by the Sanitary District before the city will accept the submittal — treat it as a parallel approval, not an afterthought.

What you can build

El Cerrito's ADU ordinance tracks California state law (updated most recently by Ordinance 2021-20), with the state baseline applying where the ordinance is silent:

El Cerrito doesn't run a preapproved ADU plan library, so the practical shortcut here is the free pre-application meeting: staff will tell you what your site needs before you pay for full plans. On hill lots, expect the city to look hard at grading, drainage, and retaining walls.

One approval most cities don't have: the Stege Sanitary District

El Cerrito sits entirely within the Stege Sanitary District, so your sewer connection gets its own agency review. Plans must carry the District's stamp before the city accepts the submittal — the city even recommends contacting the District during the planning stage. Water comes from EBMUD. Two things to get a read on early: your private sewer lateral (EBMUD and Stege both run lateral compliance programs, and the districts can flag a defective lateral during an ADU review), and the wildland-urban interface. El Cerrito's hillside neighborhoods are in the very high fire hazard severity zone, which means fire-safe construction requirements — Class A roof, ember-resistant vents, defensible space — get designed in from the start, not added at plan check.

What goes into the submittal

• One digital PDF plan set (24"x36" max): plot plan with topography (for lots with more than 5 feet of elevation change), floor plans, roof plan, exterior elevations, foundation/floor framing/roof framing details with cross sections, and mechanical, electrical, and plumbing plans.
• Sanitary District stamp on the plans — required before the city accepts the application.
• Structural calculations (wet signed and stamped) and Title 24 energy calculations and forms.
• Soils report for hillside or slope conditions.
• Site plan details: lot lines, building footprints, setbacks, easements, utilities to the curb, trees and tree canopy, plus a grading and drainage scheme — El Cerrito's checklist is particularly detailed on drainage for hill sites.

Where applications usually get stuck

• Sanitary District review is skipped. Homeowners submit to the city first and learn the District's stamp is a prerequisite — run both reviews in parallel.
• Thin topography and drainage plans. On hill lots the city wants contours, pad elevations, top and toe of slopes, and a drainage scheme — not just a flat site plan.
• Old sewer laterals flagged mid-review. A defective lateral turns into a replacement project with its own budget and schedule.
• Fire-zone requirements missed: vent screening, ignition-resistant construction, defensible space.
• Garage conversions triggering foundation, egress window, ceiling height, and fire separation requirements — it's never just "add drywall."