ADUs in El Cajon, CA
✓ Verified November 1, 2026 Rules, fees, and timelines below were verified November 1, 2026. Anything marked “confirm” or “to verify” is still open.
This page is thinner than most on this site, on purpose. El Cajon's ADU section (§17.140.180) exists and was updated in 2025, but its full text was not retrievable in this pass — so no El Cajon-specific size, height, setback, parking, or fee number is published here. What is published: the verified city facts (2025 permit count, online portal, contacts, standardized-plans program, loan program) and state-law floors labeled as state law. Everything else is marked to confirm until the code text is read.
If you cannot find an address in PACO, it is likely not within the City of El Cajon — many unincorporated San Diego County addresses have El Cajon listed as the city (city-published PACO FAQ). Confirm jurisdiction before relying on city rules.
Parcels near Gillespie Field fall under the Montgomery Field and Gillespie Field Airport Land Use Compatibility Plans for new development in noise-sensitive areas — relevant context, not an ADU-specific rule.
Does it apply to my lot? — address check
Enter a San Diego County street address. The checker geocodes it and checks public transit stops nearby. Privacy: your typed address goes directly from your browser to OpenStreetMap's free Nominatim geocoder and the public SanGIS transit-stops layer. It never touches an ADUKey server — ADUKey has no server endpoint for this, so there is nothing to send it to.
Parking-exemption rule: no parking required within a 1/2-mile walking distance of public transit (bus stops included). Straight-line distance is measured first: a straight-line miss is definitive, a straight-line hit is provisional until the walking route is checked.
What you can build
| Rule | What applies | Note |
|---|---|---|
| Detached ADU max size | To verify — code text not retrieved | To verify — full text of §17.140.180 not retrieved. Builder guides cite 1,200 sq ft (BuildGreenNH) and 1,000 sq ft for 2+ bedrooms (Tiny House Advisor) inconsistently — neither is published here as a city rule. Trap avoided: an eCode360 excerpt giving '150 to 430 square feet' describes a tiny home on wheels as a separate use class, not an ADU rule. |
| Attached ADU size | To verify — code text not retrieved | To verify — code text not retrieved. |
| Junior ADU (JADU) | To verify — city text to confirm; state baseline 500 sq ft | City-specific JADU text to confirm. State-law baseline only: JADU ≤500 sq ft; owner-occupancy required only when the JADU shares sanitation/bathroom facilities with the primary dwelling (AB 1154, eff. Jan 1, 2026). |
| Height | To verify — code text not retrieved | To verify — code text not retrieved. |
| Setbacks | To verify — code text not retrieved | To verify — code text not retrieved. State guarantee below applies regardless of local standards. |
| State-exempt ADU | 800 sq ft / 16 ft / 4 ft side and rear setbacks guaranteed by state law regardless of local limits, on a lot with an existing single-family home | State law, applies in El Cajon — not an El Cajon rule. |
| Parking | To verify — city standard not retrieved. State law: no parking may be required within a half-mile walk of public transit (bus stops included), in a historic district, as part of an existing structure, where on-street permit parking is not offered, within one block of a car-share, or for a garage conversion (no replacement parking) | To verify — the code cross-references 'parking standards for an ADU,' but the standard itself was not retrieved. Do not publish any 'no parking required' claim for El Cajon. State-law exemptions (below) apply via state law; any local additions are to confirm. |
| Minimum rental term | State floor: ADUs may not be rented for less than 30 days — city wording to confirm | City-specific rental-term wording to confirm. State-law floor only. |
| Impact fees | State floor: no impact fees on ADUs under 750 sq ft; proportional above that size — city schedule to confirm | City fee schedule to confirm. State-law floor only. |
| Permit fees | Not published — to confirm | No city-published permit/plan-review fee amounts for ADUs were found. No fee is invented here. |
| Multifamily lots | State baseline (SB 1211): up to 8 detached ADUs on a multifamily lot, plus conversion of non-livable space up to 25% of existing units — city counts to confirm | No city-stated multifamily ADU counts found. State-law baseline only; whether El Cajon's code restates, narrows, or adds to this is to confirm. |
| Overlays to check | No coastal zone, no coastal permit requirement (inland city, no certified Local Coastal Program). Fire service: Heartland Fire and Rescue (cooperative agreement with La Mesa and Lemon Grove; ISO Class 1 recertified) | Per-parcel checks required. Fire hazard severity zone for a specific parcel: to verify via CAL FIRE maps — do not import another city's zone acreage or rules. Hillside/flood ADU rules: none verified. |
Permit path
The city runs the Project Assistance Center Online (PACO) portal for permits and plan review — PACO is the submission route to name on this page; the exact PACO landing URL was not captured verbatim, so link via the city's Community Development pages rather than a guessed URL. In person: City Hall, 200 Civic Center Way, El Cajon, CA 92020; Planning counter walk-in service on the 1st floor; Project Assistance Center on the 3rd floor. Planning: 619-441-1742, planning@cityofelcajon.us. Building Safety: 619-441-1726. Business hours: Monday–Thursday 7:30 a.m.–5:00 p.m., alternating Fridays 8:00 a.m.–5:00 p.m. State law requires a ministerial decision within 60 days (Gov. Code §66321); El Cajon's own published confirmation of its ministerial-track wording was not retrieved — the 60-day figure is stated as state law only. Jurisdiction callout: PACO's FAQ states: 'If you cannot find an address in PACO, then it is likely not within the City of El Cajon. Many unincorporated San Diego County addresses have El Cajon listed as the city.'Standardized plans and ADU loan program — existence confirmed, contents unread
The city's documents listing includes 'El Cajon ADU Standardized Plans Combined' — a city-published standardized-plans document exists. The same listing includes an ADU Fact Sheet, an ADU Tenant Limits Sheet 2025, a Phase I ADU-Program pre-submittal document, and ADU Loan Program Guidelines V5. Plan sizes, plan count, cost, and review track (including whether a 30-day AB 1332 expedited track applies) were not retrievable in this pass and are to verify — do not publish until read. Separately, the city operates an ADU Loan Program: the 2025 General Plan Annual Progress Report states that during 2025 the city promoted the program and three ADU loans were initiated but not completed in 2025. Loan terms are to verify from the Guidelines V5 document.2025 ADU permits (city-published)
City-published: 210 new housing units were issued permits in 2025, which included 86 accessory dwelling units, per the 2025 General Plan Annual Progress Report (accepted by City Council March 24, 2026). Publish exactly as: '86 ADUs issued permits in 2025 (of 210 total new units permitted).' Do NOT relabel as completions — the report counts permits issued. The affordability split given for the 210 total (38 low-income, 172 moderate and above) is NOT ADU-specific and must not be attributed to ADUs. Traps avoided: a citizenportal item about an October 22, 2025 council ADU update is Yuba City (Sutter County), not El Cajon; a December 2025 item about 'Ordinance 2025-1007' detached ADUs is Nashville/Metro, not El Cajon.Separate sale (AB 1033) — to confirm
No city statement found. No El Cajon ordinance, council action, or builder-guide claim on AB 1033 adoption surfaced. Status: to confirm — publish neither 'adopted' nor 'not adopted.' The County of San Diego's AB 1033 adoption applies to unincorporated areas only, not the City of El Cajon. JADUs can never be sold separately even where AB 1033 is adopted (state law).AB 956 (effective January 1, 2027) — to confirm
No city statement found. State-law baseline (state law only): AB 956, signed September 29, 2026 and effective January 1, 2027, allows two detached ADUs per single-family lot and bars HOAs from blocking state-compliant ADUs. How El Cajon will apply it: to confirm — no city statement located.Rent calculator
Defaults below are EXAMPLES — editable placeholders, not verified local rent or cost data. Type your own numbers.
Verified builders in San Diego County
One metro-level profile per builder, linked from every city page they serve. Profiles are never duplicated per city, so a correction lands everywhere at once.
Frequently asked questions
Why does this page have no size or height numbers?
Because the full text of ECMC §17.140.180 was not retrievable in this pass — the code chapter page confirmed the section exists but the section text itself was not obtained. Builder guides cite inconsistent detached sizes (1,200 sq ft in one, 1,000 sq ft for 2+ bedrooms in another), and neither is verified against the code, so neither is published as a city rule. The page publishes what is verified (the 86-permit count, the portal, the programs) and labels state-law floors as state law, rather than filling gaps with builder numbers.
How do I submit an ADU application in El Cajon?
The city runs the Project Assistance Center Online (PACO) portal for permits and plan review — PACO is the submission route to name. In person: City Hall, 200 Civic Center Way, El Cajon, CA 92020; Planning counter walk-in service on the 1st floor; Project Assistance Center on the 3rd floor. Planning: 619-441-1742, planning@cityofelcajon.us. Building Safety: 619-441-1726. Business hours: Monday–Thursday 7:30 a.m.–5:00 p.m., alternating Fridays 8:00 a.m.–5:00 p.m. State law requires a ministerial decision within 60 days; El Cajon's own published confirmation of its ministerial-track wording was not retrieved — the 60-day figure is stated as state law only.
Does El Cajon offer standardized ADU plans?
A program exists — the city's documents listing includes 'El Cajon ADU Standardized Plans Combined' — but the document's contents were not retrievable in this pass. Plan sizes, plan count, cost (free or priced), and review track (including whether a 30-day AB 1332 expedited track applies) are to verify and are not published until read. The same listing includes an ADU Fact Sheet, an ADU Tenant Limits Sheet 2025, a Phase I pre-submittal document, and ADU Loan Program Guidelines V5.
Can I sell an ADU separately from the house in El Cajon?
No city statement found. No El Cajon ordinance, council action, or builder-guide claim on AB 1033 adoption surfaced. Status: to confirm — the page publishes neither 'adopted' nor 'not adopted.' The County of San Diego's AB 1033 adoption applies to unincorporated areas only, not the City of El Cajon.
Sources
- City of El Cajon Zoning Code Amendment page — ADU Section 17.140.180 (city-published)
- City of El Cajon 2025 General Plan Annual Progress Report, Council agenda March 24, 2026 (city-published)
- City of El Cajon standardized plans documents listing (city-published)
Not legal advice. This page is a starting point, not a parcel approval. Confirm your lot with the city before you build, buy, or sign anything.
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