San Diego ADU Regulations (2026): City-by-City Rules, Sizes & Permits
Last updated: May 2026 · Maintained by IL Total Design & Build — San Diego ADU design-build specialists, CSLB #1058676
Accessory dwelling unit (ADU) rules in San Diego County start with one statewide framework, then change city by city — mostly around maximum size, height, parking, coastal permits, and how many units you can build. This guide gives you the 2026 baseline that applies everywhere, then the local details for all 23 jurisdictions and neighborhoods we work in. Use the search box to jump to your city.
The 60-second version
- Almost every single-family lot in San Diego can build at least one ADU plus one JADU, approved ministerially (no public hearing).
- Detached ADUs are commonly allowed up to 1,200 sq ft; coastal cities like Del Mar and Solana Beach cap detached units smaller (≈850–1,000 sq ft).
- No owner-occupancy is required for ADUs (it is required for JADUs), and no replacement parking is required when you convert a garage.
- The City of San Diego is the outlier: its ADU (Home Density) Bonus Program can allow 4–6 ADUs on a single lot depending on lot size.
- Coastal-zone properties (La Jolla, Del Mar, Encinitas, Coronado, Imperial Beach, Solana Beach, parts of Carlsbad and Oceanside) usually need a Coastal Development Permit — now decided within 60 days under AB 462.
What changed for 2026
California passed its biggest batch of ADU reforms to date. The ones that affect San Diego homeowners most:
AB 1033 — Sell your ADU separatelyCities can opt in to let ADUs be sold as condos. The City of San Diego is participating.
SB 1211 — More units on multifamilyUp to 8 detached ADUs on qualifying multifamily lots; no replacement parking for removed uncovered spaces.
AB 1332 — Pre-approved plansEvery city must offer a permit-ready ADU plan program with faster (≈30-day) approval.
AB 462 — Faster coastal permitsCoastal cities must approve or deny an ADU Coastal Development Permit within 60 days.
AB 976 — Owner-occupancy ban is permanentLocal agencies cannot require you to live on-site to build an ADU (JADUs still require it).
AB 2533 — Amnesty for older unitsAn easier path to legalize unpermitted ADUs built before 2020.
The statewide baseline (applies in every city)
Unless a city has a stricter, state-compliant rule (noted in each card below), these California minimums apply across San Diego County:
| Rule | 2026 statewide standard |
|---|---|
| Detached ADU size | Cities must allow at least an 800 sq ft / 16 ft unit; most allow up to 1,200 sq ft. |
| Attached ADU size | Up to 50% of the primary home, commonly capped at 1,200 sq ft (at least 800 sq ft must be allowed). |
| Junior ADU (JADU) | Up to 500 sq ft, created within the existing/proposed home. Owner-occupancy required. |
| Height | 16 ft baseline; up to 18 ft within ½ mile of transit or on a lot with multistory multifamily; +2 ft to match the main roofline; up to 25 ft (or the zone limit) for an attached ADU. |
| Setbacks | 4 ft side and rear; 0 ft when converting an existing structure. |
| Parking | Max 1 space per ADU; waived within ½-mile walking distance of transit, in historic districts, and several other cases. No replacement parking for garage conversions. |
| Units allowed | At least 1 ADU + 1 JADU per single-family lot; up to 8 detached ADUs on qualifying multifamily lots. |
| Owner-occupancy | Not required for ADUs; required for JADUs. No rentals under 30 days. |
| Approval | Ministerial (no hearing), within ~60 days — about 30 days for pre-approved plans. |
ADU rules by city & neighborhood
City of San Diego
City of San DiegoADU Bonus Program
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | Up to 4–6 ADUs via the ADU (Home Density) Bonus Program, by lot size |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Required in coastal neighborhoods (e.g. La Jolla, PB, OB) |
Local notes: The most permissive ADU jurisdiction in the county. The ADU Home Density Bonus Program allows up to 4 ADUs on lots ≤8,000 sq ft, 5 on 8,001–10,000 sq ft, and 6 on lots over 10,000 sq ft (a deed-restricted affordable unit is paired with each bonus unit). Bonus/affordable units under 750 sq ft pay a Community Enhancement Fee and require fire sprinklers. Program rules are being refined in 2025–2026 — see Information Bulletin 400. Confirm current terms before you design.
La Jolla
City of San Diego (coastal neighborhood)Coastal zone
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Yes — Coastal Development Permit (60-day review under AB 462) |
Local notes: La Jolla is governed by City of San Diego ADU rules, but nearly all of it sits in the Coastal Zone, so a Coastal Development Permit is usually required, and bluff/slope sensitivity can affect height and siting. Highest ADU ROI in the county — and the most design-sensitive.
Carmel Valley
City of San Diego (Carmel Valley Precise Plan)
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: A City of San Diego neighborhood under the Carmel Valley Precise Plan. City ADU rules apply, but HOA / planned-community design review is common here and can govern materials, color and placement. Check your CC&Rs early.
Scripps Ranch
City of San Diego (neighborhood)
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: City of San Diego ADU rules apply. Many Scripps Ranch communities have active HOAs with architectural review and larger lots — both shape what you can build. Confirm CC&Rs alongside city rules.
Unincorporated County
County of San Diego (PDS)
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear (0 ft for single-story under 16 ft, per fire code) |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Required only in the small unincorporated coastal areas |
Local notes: Covers communities like Spring Valley, Bonita, Lakeside, Fallbrook, Alpine, Valley Center and more. Larger rural lots can support bigger detached ADUs where lot coverage and FAR allow. See the County PDS ADU Handbook.
Rancho Santa Fe
County of San Diego + RSF Covenant
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Undetermined in the small coastal-zone portion |
Local notes: Mostly unincorporated County jurisdiction — but the Rancho Santa Fe Association (the Covenant) enforces strict private design review that often controls the look and siting of an ADU more than county rules do. Very large lots; plan for the Covenant's Art Jury process.
Del Mar
City of Del MarCoastal zone
| Max detached ADU | 850 sq ft (1-bed) / 1,000 sq ft (2+ beds) |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (reduced to 14 ft in bluff/slope/canyon-sensitive areas) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Yes — citywide Coastal Zone (CDP required) |
Local notes: Allowed in all residential zones except RM-South. Smaller size caps and tight height limits in sensitive areas make design expertise essential here. ADU square footage counts toward the lot's floor-area ratio (FAR).
Solana Beach
City of Solana BeachCoastal zone
| Max detached ADU | 850 sq ft (studio/1-bed) / 1,000 sq ft (2+ beds) |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; 20 ft to match roof); up to 25 ft / house height if attached |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Yes — citywide Coastal Zone (CDP required) |
Local notes: Entirely within the Coastal Zone, so a CDP is required for essentially every ADU. Detached size caps mirror the smaller coastal-city pattern.
Encinitas
City of EncinitasCoastal zone
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial; faster via the PRADU permit-ready program |
| Coastal permit | Required for coastal-zone parcels |
Local notes: Home of the PRADU (Permit-Ready ADU) program — pre-designed, customizable plans with most plan-check and building-permit fees waived. One of the top jurisdictions in the county for ADU permits issued. Coastal parcels still need a CDP.
Oceanside
City of OceansideCoastal zone
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home or 1,200 sq ft (min 800 sq ft) |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Required for coastal-zone parcels |
Local notes: Detached units up to 1,200 sq ft; JADUs up to 500 sq ft. 60-day building-permit review; rentals must be 30+ days (no short-term rentals).
Carlsbad
City of CarlsbadCoastal zone
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Required for coastal-zone parcels |
Local notes: Carlsbad updated its ADU ordinance (size, parking and unit limits) to match recent state law including SB 1211 and AB 2533. Sizes and heights follow the state baseline; large coastal areas require a CDP.
Coronado
City of CoronadoCoastal zone
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Yes — citywide Coastal Zone (CDP required) |
Local notes: The entire island is in the Coastal Zone, so a CDP is the norm. Small lots and a historic-character context make siting tight — confirm Coronado's current local size and height specifics before you design.
Imperial Beach
City of Imperial BeachCoastal zone
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Yes — citywide Coastal Zone (CDP required) |
Local notes: Coastal city; CDP generally required. Rules otherwise track the state baseline — confirm Imperial Beach's local specifics for your parcel.
Chula Vista
City of Chula Vista
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: County's second-largest city. State baseline applies; many eastern master-planned communities have HOAs and design review that add requirements. Confirm CC&Rs in addition to city rules.
Escondido
City of Escondido
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: Inland city following the state baseline. Larger and semi-rural lots can support bigger detached ADUs where lot coverage and FAR allow.
El Cajon
City of El Cajon
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: Inland East County city; state baseline applies. Confirm El Cajon's local size/height specifics for your zone.
La Mesa
City of La Mesa
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: State baseline applies. Hillside lots and older neighborhoods can affect siting and access — worth a feasibility check.
Lemon Grove
City of Lemon Grove
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: Small East County city; state baseline applies. Confirm current local specifics for your parcel.
Santee
City of Santee
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: Inland city following the state baseline. Some areas have HOAs and floodplain considerations — confirm before design.
San Marcos
City of San Marcos
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: North County inland city; state baseline applies. Hillside and planned-community areas may add design review.
Vista
City of Vista
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: North County inland city following the state baseline. Confirm Vista's local specifics for your zone.
Poway
City of Poway
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: Known as "the City in the Country." State baseline applies, but large semi-rural lots and the Rancho/RR zones can allow bigger detached ADUs — and may carry additional rural design and access standards.
National City
City of National City
| Max detached ADU | Up to 1,200 sq ft |
|---|---|
| Max attached ADU | 50% of primary home, up to ~1,200 sq ft |
| Junior ADU (JADU) | Up to 500 sq ft (owner-occupancy required) |
| Height | 16 ft (18 ft near transit; up to 25 ft if attached) |
| Setbacks | 4 ft side & rear; 0 ft for conversions |
| Parking | 1 space/ADU; waived ½ mi from transit; none for garage conversions |
| ADUs allowed | ≥1 ADU + 1 JADU per single-family lot |
| Owner-occupancy | Not required for ADUs; required for JADUs |
| Approval | Ministerial, ~60 days |
| Coastal permit | Not typically required (inland) |
Local notes: Compact, transit-rich South Bay city — meaning parking is frequently waived (½-mile transit rule). State baseline otherwise applies.
Not sure which rules apply to your lot?
Zoning overlays, coastal boundaries, transit distance and HOA covenants change what you can actually build — often more than the city limits do. We confirm your exact, current rules and what fits your property in a free feasibility check.
Get your free feasibility check →Frequently asked questions
How big can an ADU be in San Diego?
Most San Diego jurisdictions allow a detached ADU up to 1,200 sq ft. Attached ADUs are limited to 50% of the primary home (commonly up to 1,200 sq ft), and a Junior ADU is capped at 500 sq ft. Coastal cities such as Del Mar and Solana Beach cap detached ADUs smaller — roughly 850 sq ft for a one-bedroom and 1,000 sq ft for two or more bedrooms.
How many ADUs can I build on my property in the City of San Diego?
Under the City of San Diego's ADU (Home Density) Bonus Program, you can build up to 4 ADUs on lots up to 8,000 sq ft, 5 on lots of 8,001–10,000 sq ft, and 6 on lots over 10,000 sq ft. Each market-rate bonus unit must be paired with a deed-restricted affordable unit. The program is being refined in 2025–2026, so confirm current terms before designing.
Do I have to live on the property to build an ADU?
No. California law (made permanent by AB 976) prohibits cities from requiring owner-occupancy to build an ADU, so investors and owners of rental property can build. Junior ADUs (JADUs) are the exception — they still require the owner to live in one of the units.
Do I need to add parking for an ADU?
Often not. No additional parking is required if your ADU is within a half-mile walking distance of public transit, in a historic district, or in several other situations. When parking can be required, it's capped at one space per ADU. Importantly, you do not have to replace parking when converting a garage into an ADU.
What are the setback requirements for an ADU?
State law requires only 4-foot side and rear setbacks for a new detached ADU, and no setback when you convert an existing structure (like a garage). Front setbacks follow your underlying zone.
How tall can an ADU be?
The baseline is 16 feet, rising to 18 feet if your lot is within a half-mile of transit or has multistory multifamily housing, plus up to 2 extra feet to match your main home's roofline. An attached ADU can generally go up to 25 feet or the zone's height limit. Some coastal and sensitive areas (e.g., Del Mar bluffs) reduce this to about 14 feet.
Can I sell my ADU separately from my house?
In participating cities you can. AB 1033 lets local agencies allow ADUs to be sold separately as condominiums, and the City of San Diego is participating. It involves recording a condo plan, separate utility metering, and creating an HOA — so it's more involved than a standard ADU.
Do I need a Coastal Development Permit for my ADU?
If your property is in the Coastal Zone — which covers all of Del Mar, Solana Beach, Coronado and Imperial Beach, plus coastal parts of San Diego (La Jolla, Pacific Beach, Ocean Beach), Encinitas, Carlsbad and Oceanside — you'll typically need a Coastal Development Permit. As of AB 462, cities with a certified Local Coastal Program must decide these within 60 days.
How long does ADU approval take in San Diego?
ADUs are approved ministerially (no public hearing), and state law requires a decision within about 60 days of a complete application — roughly 30 days if you use a city's pre-approved (permit-ready) plan program. Coastal Development Permits add their own 60-day timeline. Construction is a separate phase.
What's the difference between an ADU and a JADU?
An ADU is a fully independent dwelling with its own kitchen, bathroom and entrance, up to 1,200 sq ft. A Junior ADU (JADU) is smaller — up to 500 sq ft — must be created within the walls of the existing home, can share a bathroom, and requires the owner to live on the property. Many lots can have one of each.
Did San Diego ADU laws change in 2026?
Yes. Recent California laws expanded what's allowed: AB 1033 (sell ADUs as condos), SB 1211 (up to 8 ADUs on multifamily lots), AB 1332 (mandatory pre-approved plan programs), AB 462 (60-day coastal permits and fire-rebuild relief), AB 976 (permanent owner-occupancy ban) and AB 2533 (amnesty for older unpermitted units).
Important: This guide is for general information, not legal advice, and ADU rules change frequently as the State of California and local jurisdictions update their ordinances. Figures reflect our reading of state law and local ordinances as of May 2026; some local specifics vary by lot and overlay. Always confirm current requirements with the governing jurisdiction — or let us verify them for you. IL Total Design & Build, CSLB #1058676.
Primary sources: California HCD ADU Handbook (2026 update); City of San Diego Development Services Information Bulletin 400 & ADU Bonus Program; County of San Diego PDS ADU Handbook; and the planning departments of Del Mar, Encinitas, Oceanside, Carlsbad, Solana Beach, Coronado and other named jurisdictions.