ADUs in Imperial Beach, CA
✓ Verified November 1, 2026 Rules, fees, and timelines below were verified November 1, 2026. Anything marked “confirm” or “to verify” is still open.
A mailing address that says “Imperial Beach” does not guarantee the parcel is under City of Imperial Beach rules. Confirm jurisdiction before relying on anything on this page.
Defining fact: about 87% of the city lies in the Coastal Zone. Imperial Beach is the coastal-permit city — the coastal permit is usually the first permit in the sequence, not an afterthought.
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 size | Up to 1,200 sq ft | |
| Attached ADU size | 50% of the primary dwelling, max 1,200 sq ft | |
| Junior ADU (JADU) | Up to 500 sq ft | |
| Practical minimum size | 150 sq ft | |
| Height | 16 ft (two stories in some situations) | |
| Side / rear setbacks | 4 ft | |
| Building separation | 10 ft between the primary dwelling and a detached ADU | One guide cites 6 ft — confirm. |
| Parking | 1 space per ADU when required, waivable | State exemptions apply. |
| Owner-occupancy | None for standard ADUs; required for JADUs | |
| Minimum rental term | 30 days | |
| Multifamily (SB 1211, eff. Jan 1, 2025) | At least 2 detached ADUs where a multifamily building exists, up to the number of existing units, max 8; conversions of non-habitable space up to 25% of units, minimum 1 | |
Coastal permits: the defining process
Triggers (city handout): a new attached ADU in the Coastal Zone; a new detached ADU in the Coastal Zone; conversion of existing permitted uninhabitable space (garage, storage, patio cover) into an ADU in the Coastal Zone; a garage-to-JADU conversion in the Coastal Zone.
Jurisdiction (City Parcel Viewer, Coastal Zone Jurisdiction layer): Green Zone — city-issued administrative coastal permit; Red Zone — city-issued, Coastal Commission can appeal; Blue Zone — Coastal Commission jurisdiction (permit through the Commission, not the city). Check your parcel at imperialbeachca.mapgeo.io.
Sequence: the coastal permit must be approved before the building permit application; concurrent processing is available. Review time: 30 calendar days from payment.
Fee: $1,000 city Developer Fee, per the current city handout and CDP checklist. General coastal development permits: $2,323 administrative / $5,807 public hearing; oceanfront parcels: coastal engineering study plus a $1,200 starting deposit.
Discrepancy note: older builder guides cite about $600 for the coastal fee. This page uses the city's current $1,000 figure.
Pre-approved 600 sq ft plan (PDS 671)
The city offers a pre-approved 600 sq ft ADU plan (plan set PDS 671) with checklist guidance. It cannot be used in a flood hazard area. Solar PV is a deferred submittal. A soils-report waiver-request process exists; the soils requirement itself is not explicit — confirm.
Digital submission, timelines, and costs
Submit digitally through the City's online Citizen Self-Service (EnerGov) portal — no in-person requirement. Permits typically take 4–6 months per builder guides (Better Place: online review 2–6 months, issuance 6–12 months; full project 10–12 months). Permit costs run about $8–10 per sq ft. Construction: $300,000–$450,000+.
Separate sale (AB 1033): not adopted
Separate sale under AB 1033 was not adopted as of March 2025. Confirm — this changes fast.
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
Do I need a coastal permit for an ADU in Imperial Beach?
Almost certainly yes. About 87% of the city is in the Coastal Zone, and a coastal permit is triggered by a new attached or detached ADU, a conversion of permitted uninhabitable space into an ADU, or a garage-to-JADU conversion inside the zone. The coastal permit must be approved before you apply for a building permit.
What does the coastal permit cost?
$1,000 city Developer Fee, per the current city handout and CDP checklist. Older builder guides cite about $600 — this page uses the city's $1,000 figure. Review time is 30 calendar days from payment.
Can I sell an Imperial Beach ADU separately?
Not as of March 2025 — the city had no AB 1033 ordinance then. Confirm, because this changes fast.
Does Imperial Beach offer a pre-approved plan?
Yes — the city offers a pre-approved 600 sq ft ADU plan (plan set PDS 671) with checklist guidance. It cannot be used in a flood hazard area, and solar PV is a deferred submittal.
Sources
- City of Imperial Beach ADU handout and CDP checklist (coastal fee $1,000; 30-day review)
- City of Imperial Beach Parcel Viewer — imperialbeachca.mapgeo.io (Coastal Zone Jurisdiction layer)
- City pre-approved 600 sq ft ADU plan, plan set PDS 671
- Builder guides — timelines and costs (including the older ~$600 coastal-fee figure)
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.
Report an outdated rule
Rules change. If something on this page no longer matches the city's current rules, tell us what changed and where you saw it. Reporting is not wired to a destination yet — your note stays on this page and is not sent anywhere.