How San Diego Handles Accessory Structures: A Practical Guide

San Diego maintains 241 local ordinances across all categories, and 9 of those deal specifically with accessory structures. Here is a breakdown of what the city actually requires, what is prohibited, and where San Diego falls on the strict-to-permissive spectrum compared to other cities.

Carport Rules

Carports in San Diego are permitted as accessory structures in residential zones. Carports and patio covers up to 300 square feet of projected roof area that are accessory to single-family homes are generally exempt from building permits if they maintain minimum 6-foot clearance from other such structures and at least 3 feet from property lines. Larger carports require building permits and must comply with zoning setback requirements.

Key details: Permit Exempt: Up to 300 sq ft with proper clearances. Clearance: 6 ft from other patio covers/carports; 3 ft from property lines. Larger Carports: Building permit required if over 300 sq ft. Setbacks: Must comply with zoning setback regulations. Solar: Solar panels on carports may need separate permit.

Unpermitted carports: stop-work orders, required removal or retroactive permitting with penalty fees. Fines $200 to $1,000.

ADU Permits

San Diego processes ADU permits ministerially (over-the-counter, no discretionary review) under SDMC § 141.0302 and California Government Code § 65852.2. Applications are filed with the Development Services Department through OpenDSD. State law caps review at 60 days. San Diego offers pre-approved ADU plan sets, which can shorten review to a few weeks.

Key details: Code Section: SDMC § 141.0302; Gov. Code § 65852.2. Review: Ministerial, 60-day cap (state law). Detached Max: 1,200 sq ft (state by-right 800). Pre-Approved Plans: 3–4 week turnaround. Portal: OpenDSD.

Unpermitted ADU construction triggers stop-work orders and code enforcement under SDMC Ch. 12. Building without permits is a misdemeanor with fines up to $1,000 and/or 6 months in jail. Daily fines accrue until correction. Unpermitted work blocks insurance and sale closings.

If you are coming from a city with tighter rules, you will find San Diego gives residents more flexibility on adu permits.

ADU Impact Fees

San Diego exempts ADUs under 750 square feet from all impact fees per California Government Code § 65852.2(f). ADUs 750 sq ft or larger pay impact fees proportionate to the principal dwelling's square footage. Affordable ADUs deed-restricted for low/moderate-income tenants receive additional fee waivers. School fees are separately governed by SB 13 (2019) and state law.

Key details: Under 750 sq ft: ALL impact fees waived (state law). 750+ sq ft: Proportional to principal dwelling. State Law: Gov. Code § 65852.2(f). Affordable Bonus: Additional waivers for deed-restricted ADUs. School Fees: Proportional under SB 13.

Failure to pay required permit and impact fees results in permit denial. Misrepresenting square footage to claim the under-750 exemption is fraud and can void the permit and Certificate of Occupancy.

If you are coming from a city with tighter rules, you will find San Diego gives residents more flexibility on adu impact fees.

ADU Owner Occupancy

San Diego does NOT require owner occupancy for ADUs built between January 1, 2020 and December 31, 2024 under California Government Code § 65852.2(a)(6). For ADUs permitted in 2025 and later, AB 976 (extending the moratorium) and AB 1033 (allowing condo conversion) keep most owner-occupancy bans in place. Junior ADUs (JADUs) still require owner occupancy on the property per SDMC § 141.0302(c).

Key details: Standard ADU: No owner-occupancy required (state law). JADU: Owner occupancy required (SDMC § 141.0302(c)). State Law: Gov. Code § 65852.2(a)(6); AB 976. Condo Conversion: Not adopted by San Diego (AB 1033).

No owner-occupancy enforcement for standard ADUs (state law preempts). JADU owner-occupancy violations can result in revocation of the certificate of occupancy and code enforcement under SDMC Ch. 12. Misrepresenting JADU occupancy is a misdemeanor.

If you are coming from a city with tighter rules, you will find San Diego gives residents more flexibility on adu owner occupancy.

ADU Rental Restrictions

San Diego ADUs may be rented long-term (30+ days) without restriction. Short-term rentals are governed by SDMC § 510.0101 et seq. (the four-tier STRO program). ADUs cannot operate as Tier 3 or Tier 4 STRs in most cases because those tiers require the host's primary residence. Junior ADUs are restricted to 30-day minimum rentals by SDMC § 141.0302(c)(2).

Key details: Long-Term (30+ days): Permitted, no separate license. STR Tiers: 1-4 under SDMC § 510. ADU as Tier 3/4: Generally not eligible. JADU STR: Banned (30-day minimum). STRO Code: SDMC § 510.0101 et seq..

Operating an unlicensed STR carries administrative fines up to $1,000 per violation under SDMC § 510. Repeat violations can result in tier downgrades or permit revocation for 5 years. JADU short-term rental violations can void the ADU permit. The city actively monitors Airbnb/VRBO listings against the licensed database.

This is not one of those rules that cities tend to ignore. San Diego actively enforces its adu rental restrictions requirements.

Garage Conversions

San Diego permits garage conversions to ADUs under state law (Government Code 65852.2) without requiring replacement parking. Conversions must meet Building Code standards for habitable space including egress, ventilation, insulation, and fire separation. Permits required through Development Services.

Key details: Replacement Parking: Not required. Ceiling Height: 7 feet minimum. Permit Required: Yes, through DSD. Impact Fees: Waived under 750 sq ft. Code: CA Gov Code 65852.2 + SDMC.

Unpermitted conversions subject to code enforcement and double permit fees. Non-compliant conversions may be ordered restored to original condition or brought into compliance.

Shed Rules

San Diego exempts detached accessory structures (sheds) under 120 square feet and one story from building permits under SDMC 129.0202. Sheds must comply with setback requirements. Larger sheds require permits. Structures may not be used as habitable space without ADU approval.

Key details: Permit Exempt: Under 120 sq ft, 1 story. Setbacks: 3-5 ft from property lines. Front Yard: Not permitted. Habitable Use: Requires ADU permit. Code Section: SDMC 129.0202.

Unpermitted structures over 120 sq ft subject to double permit fees. Sheds used as habitable space may be red-tagged and ordered vacated. Non-compliant structures may be ordered removed.

ADU Rules

San Diego permits ADUs under SDMC Chapter 14, Article 1, Division 3, consistent with California ADU law (Government Code 65852.2). Single-family lots may have one ADU, one JADU, and one converted ADU. No owner-occupancy requirement. Permit timeline typically 3-5 months. SB 1211 (2024) allows up to 8 ADUs.

Key details: Max Detached ADU: 1,200 sq ft. JADU Size: 150-500 sq ft. Rear/Side Setback: 4 feet. Parking: Not required. SB 1211 (2025): Up to 8 ADUs.

Unpermitted ADUs subject to code enforcement. The City offers a process to legalize unpermitted ADUs under Information Bulletin 242. Fines for unpermitted construction.

Tiny Homes

Tiny homes in San Diego are most commonly permitted as Accessory Dwelling Units (ADUs) under SDMC Chapter 14, Article 1, Division 3. Detached ADUs may be up to 1,200 sq ft; units 800 sq ft or smaller are exempt from lot coverage, FAR, and open-space requirements. ADUs up to 16 ft tall may be built at side and rear property lines; taller ADUs require 4-ft setbacks. The minimum ADU size is 150 sq ft. Tiny homes on wheels are not recognized as permanent housing.

Key details: ADU Framework: SDMC Ch. 14, Art. 1, Div. 3. Max Size: 1,200 sq ft for detached ADU. Min Size: 150 sq ft. Small ADU Bonus: Under 800 sq ft: exempt from lot coverage/FAR/open space. Height: Up to 16 ft at property line; taller with 4-ft setback.

Unpermitted dwellings: removal or retroactive permitting. Zoning violations: fines and required relocation. Occupancy without certificate: prohibited.

The Bottom Line

Compared to many U.S. cities, San Diego gives residents more room on accessory structures. 3 of the 9 rules here are rated permissive. But permissive does not mean unregulated. There are still requirements, and the city does enforce them when violations are reported.

All of the above reflects San Diego's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.