What is a JADU and how is it different from an ADU?

A JADU (Junior ADU) is a unit up to 500 sqft built inside the footprint of an existing single-family house — usually a converted bedroom or garage. It requires owner-occupancy and is faster/cheaper to permit than a full ADU.

Can I have both a JADU and an ADU on my LA lot?

Yes — state law allows one JADU plus one ADU on most single-family lots in LA. The combination is often the best path for multi-generational living plus rental income.

Can my Irvine HOA block an ADU?

No. State law preempts HOA prohibition of ADUs. The HOA can review materials and elevations, but cannot deny the permit outright.

Do I need a CDP for a Newport Beach ADU?

Most of Newport's Balboa Peninsula and oceanfront sit in the Coastal Zone, requiring a CDP. Inland Newport parcels typically do not.

Orange County JADU Builder.

A Junior ADU carves up to 500 sqft out of an existing single-family house, typically a converted bedroom or attached garage bay. It is the lightest-touch path to a permitted rental unit in LA — and the owner can keep occupying the main house. We handle the plan set, the LADBS permit, and the build.

Orange County permits are quick when the parcel is in a streamlined city (Irvine, Anaheim, Santa Ana) and slower when the city is small and beachfront (Laguna, Newport's Balboa Peninsula). The most common schedule risk is the master-planned-community HOA — the building permit is fast, but the architectural review committee runs on its own monthly schedule.

Orange County cost band — 2026

$95K – $180K all-in

Existing plumbing wall proximity and whether the entrance already exists drive the band.

Orange County permit clock

6–10 weeks ministerial

Plan on 6–10 weeks for design + LADBS permit, then 8–12 weeks on-site.

Scope — start to keys.

Feasibility check — interior wall layout, plumbing access, exterior entry
Kitchenette, efficiency bath, and bedroom buildout
Separate exterior entrance, fire-rated demising wall if required
Owner-occupancy deed restriction and LADBS sign-off
Sub-panel, plumbing tie-in, mini-split HVAC

What changes about the permit here.

Irvine, Anaheim, Santa Ana: online ADU portals, typically 6–8 weeks ministerial.
Coastal Zone in Laguna, Newport, parts of Huntington — CDP may be required.
Master-planned-community HOAs review independently of city building & safety.
Newport-Inglewood Fault Zone parcels need an Alquist-Priolo geotech investigation.

What moves the Orange County number.

Master-planned HOA design review pushes architectural / cladding budgets 15–25% higher.
Coastal Zone CDP in Laguna / Newport adds $20–60k in soft costs and timeline.
Alquist-Priolo geotech (Newport-Inglewood) commonly $12–30k.
Irvine / Anaheim labor cost runs at LA County median.

In short.

What is a JADU and how is it different from an ADU?: A JADU (Junior ADU) is a unit up to 500 sqft built inside the footprint of an existing single-family house — usually a converted bedroom or garage. It requires owner-occupancy and is faster/cheaper to permit than a full ADU.
Can I have both a JADU and an ADU on my LA lot?: Yes — state law allows one JADU plus one ADU on most single-family lots in LA. The combination is often the best path for multi-generational living plus rental income.
How much does a JADU cost in Los Angeles?: Most LA JADUs land between $95K and $180K all-in. Existing plumbing proximity and whether the entrance already exists are the biggest swing factors.
Can my Irvine HOA block an ADU?: No. State law preempts HOA prohibition of ADUs. The HOA can review materials and elevations, but cannot deny the permit outright.
Do I need a CDP for a Newport Beach ADU?: Most of Newport's Balboa Peninsula and oceanfront sit in the Coastal Zone, requiring a CDP. Inland Newport parcels typically do not.

More we build in Orange County.

JADU Builder in nearby LA areas.

Got a Orange County project in mind?

Send us the address and we’ll pull Orange County zoning, setbacks, and jadu builder feasibility before you spend on drawings.

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