If your San Diego property is inside the California Coastal Zone, building an ADU can involve an extra layer of coastal permitting. AB 462, effective October 10, 2025, shortened the review timeline for qualifying Coastal Development Permit applications and removed a major appeal step for ADU-only projects. The Coastal Act still applies, so the exact process depends on the property's location, Local Coastal Program, coastal hazards, and other site conditions.
What this guide covers
This page focuses specifically on coastal ADU permitting in San Diego County and the 2026 rules that matter to homeowners.
- What AB 462 changed for qualifying coastal ADUs and JADUs
- What the law did not change under the California Coastal Act
- How the process differs in certified and uncertified Local Coastal Program areas
- Current City of San Diego coastal ADU guidance
- What to check before starting ADU design
Is My Property in the Coastal Zone?
The California Coastal Zone is defined by mapped legal boundaries. It is not simply every property near the beach, every lot west of Interstate 5, or every property in a coastal city.
The boundary changes significantly by location. Coastal-zone areas exist in and around La Jolla, Pacific Beach, Mission Beach, Ocean Beach, Point Loma, Coronado, Del Mar, Solana Beach, Encinitas, Carlsbad, Oceanside, Imperial Beach, and other parts of San Diego County, but the exact parcel should be verified before you plan around coastal-permit rules.
The California Coastal Commission provides official Coastal Zone and Local Coastal Program maps. These tools are useful for early screening, but a parcel close to a boundary may still require a formal jurisdiction or boundary determination.
What AB 462 Changed for Coastal ADUs
AB 462 took effect immediately when it was signed on October 10, 2025. It amended California's ADU law for qualifying Coastal Development Permit applications while leaving the Coastal Act itself in place.
A local government must approve or deny a complete qualifying Coastal Development Permit application for an ADU or JADU within 60 days.
Where the applicable local government does not have a certified Local Coastal Program and the Coastal Commission is the permitting authority, the Commission must approve or deny the complete qualifying CDP application within 60 days.
The coastal permit process and the state ADU permitting process are intended to proceed at the same time rather than as two sequential review tracks.
A qualifying locally approved CDP for an ADU-only or JADU-only project is no longer appealable to the California Coastal Commission.
Current state ADU law also says local governments are not required to hold public hearings for qualifying ADU Coastal Development Permit applications.
The 60-day rule applies to a complete Coastal Development Permit application. It should not be read as a promise that the entire ADU project, all building permits, corrections, outside-agency reviews, and construction preparation will be complete within 60 days.
Certified Local Coastal Programs Matter
The permitting path depends partly on whether the area is governed by a certified Local Coastal Program, often called an LCP.
Where a certified LCP applies, the local government generally administers coastal permitting under that certified program. In an area without a certified LCP, in an area of deferred certification, or where the Coastal Commission has retained permit jurisdiction, the Commission may be the permitting authority.
This distinction matters in San Diego County. For example, Coastal Commission materials in 2026 continue to identify Solana Beach as an uncertified jurisdiction. Other jurisdictions may also contain limited areas where certification is deferred or Commission jurisdiction is retained.
What AB 462 Did Not Change
AB 462 did not eliminate the California Coastal Act, and it did not make every coastal ADU automatically approvable.
Depending on the property and applicable coastal rules, an ADU project may still need to address coastal hazards, bluff stability and setbacks, public coastal access, wetlands or sensitive habitat, public views where protected by an applicable LCP, flooding and sea-level-rise hazards, geotechnical conditions, fire requirements, and other development standards.
Not every property will face every issue. The point is that AB 462 changed the process and timing for qualifying CDP applications; it did not erase parcel-specific coastal resource protections.
When Might a Coastal ADU Not Need a Separate CDP?
The answer depends on the jurisdiction, parcel, and project design. Homeowners should not assume an exemption based only on distance from the shoreline or bluff.
The City of San Diego currently states that a Coastal Development Permit is required for ADUs and JADUs in the Coastal Overlay Zone when the project is not completely contained within the existing primary structure, increases habitable area, or converts non-habitable space.
A project that is completely contained within the existing primary structure may have a different coastal-permit path. The City also notes that qualifying JADUs may meet Coastal Development Permit exemption criteria under San Diego Municipal Code §126.0704.
Because exemption treatment depends on the exact project and parcel, confirm the current path with Development Services before relying on an exemption.
How Coastal ADU Permitting Varies Around San Diego County
Coastal ADU permitting is not identical across San Diego County. Jurisdictions have different Local Coastal Programs, some areas remain under Coastal Commission jurisdiction, and site conditions vary from parcel to parcel.
| Area / Jurisdiction | What to verify before design |
|---|---|
| City of San Diego coastal areas | Confirm Coastal Overlay Zone status, the applicable LCP segment, City CDP requirements, and whether any retained or deferred Commission jurisdiction affects the parcel. |
| Solana Beach | Confirm the current permitting authority. Coastal Commission materials in 2026 identify Solana Beach as an uncertified LCP jurisdiction. |
| Encinitas / Cardiff / Leucadia | Check the certified LCP, mapped Coastal Zone boundary, coastal resource constraints, and parcel-specific development standards. |
| Del Mar | Check the local LCP and the coastal standards that apply to the individual property. |
| Coronado | Confirm the applicable LCP provisions and project-specific development requirements. |
| Carlsbad / Oceanside | Verify whether the specific property is within the mapped Coastal Zone and which certified LCP segment or other coastal jurisdiction applies. |
| Imperial Beach | Verify mapped Coastal Zone status, local coastal requirements, and any parcel-specific coastal constraints. |
A shorter and more predictable coastal review can reduce delay risk and carrying costs, but the actual financial effect depends on the jurisdiction, completeness of the application, site conditions, other permits, financing, design revisions, and the construction schedule. There is no single savings figure that applies to every coastal ADU.
The Coastal Commission Published New ADU Guidance in July 2026
The California Coastal Commission published final guidance on processing Local Coastal Program amendments for ADUs and JADUs in July 2026.
This guidance was required by SB 1077, not AB 462. Its main purpose is to help coastal cities and counties update older LCP provisions so local coastal rules better align with current state ADU law while still protecting coastal resources and public access.
The guidance discusses streamlined LCP amendments, updating outdated coastal ADU rules, use of minor and de minimis LCP amendments where appropriate, possible categorical exclusion orders for ADUs in locations where they would not significantly affect coastal resources, and coordination among local governments, HCD, and the Coastal Commission.
The guidance does not automatically change the permit requirement for every individual San Diego property. Local LCP language, Commission jurisdiction, parcel conditions, and current state law still need to be considered together.
Planning a Coastal ADU in San Diego: Where to Start
- Confirm the parcel's Coastal Zone statusUse official mapping and parcel information, not just the neighborhood name or distance from Interstate 5.
- Identify the permitting authorityDetermine whether the local government operates under a certified LCP or whether Coastal Commission jurisdiction may apply.
- Review property constraintsCheck the coastal, bluff, habitat, public-access, flood, view, historic, fire, geotechnical, and other conditions that actually apply to the property.
- Design the ADU around the applicable rulesAccount for state ADU law, local development standards, coastal requirements, utilities, access, and site conditions. A detached ADU may have different site-planning constraints than a conversion or attached unit.
- Submit a complete permit packageThe AB 462 coastal clock applies to a completed qualifying CDP application, so complete plans and supporting documentation matter.
For a broader look at the non-coastal rules that also affect these projects, see our San Diego ADU regulations. If you are comparing budgets, our ADU cost guide explains the main construction cost drivers. You can also see our San Diego ADU projects.
Planning an ADU in San Diego's Coastal Zone?
IL Total Design & Build can review your property's location, ADU goals, site constraints, and the permitting path that may apply before you commit to full plans.
Get a free feasibility check Call (619) 404-0125Coastal ADU & AB 462 FAQ
What did AB 462 change for coastal ADUs?
Did AB 462 eliminate Coastal Development Permits for ADUs?
Is every San Diego property west of I-5 in the Coastal Zone?
Does a coastal ADU have to be approved in 60 days?
Can a Coastal Development Permit for an ADU still be appealed to the Coastal Commission?
Does the City of San Diego require a CDP for every coastal ADU?
What changed in the Coastal Commission's July 2026 ADU guidance?
Keep exploring
Not legal advice. This article summarizes current coastal ADU rules for general informational purposes. Coastal permitting depends on jurisdiction, property conditions, applicable Local Coastal Program provisions, and current state and local rules. IL Total Design & Build provides design, permitting coordination, and construction services and is not a law firm or government permitting authority. Prepared by IL Total Design & Build, CSLB #1058676. Last updated October 2026.
