How much does an ADU cost in Los Angeles in 2026?

Most detached LA ADUs land between $300K and $500K all-in. Garage conversions typically run $160K–$260K. We hand over a one-page feasibility note with a real number before any contract.

Do you handle LADBS permits?

Yes — full plan set, structural calcs, Title 24 energy compliance, and the LADBS back-and-forth so the homeowner only signs at the milestones.

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 ADU Builder.

We design, permit, and build accessory dwelling units across Greater Los Angeles — detached backyard ADUs, attached additions, garage conversions, and JADUs. One team, one number to call, from the first feasibility walk through the final LADBS inspection.

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

$425 – $575 / sqft installed

Lot access, slab condition, panel upgrade, and finish level move the number most. Pre-approved plans trim 5–10%.

Orange County permit clock

6–10 weeks ministerial

Plan on 3–5 months for design + LADBS permit, then 4–6 months on-site for an 800–1,000 sqft detached ADU.

Scope — start to keys.

Site walk, feasibility note, and zoning / LAR1 / RD overlay check
Full architectural plan set, structural, MEP, Title 24 energy
LADBS or local-city permit submittal and back-and-forth
Foundation, framing, MEP rough, finishes, landscape tie-in
Final inspection, certificate of occupancy, and warranty

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.

How much does an ADU cost in Los Angeles in 2026?: Most detached LA ADUs land between $300K and $500K all-in. Garage conversions typically run $160K–$260K. We hand over a one-page feasibility note with a real number before any contract.
Do you handle LADBS permits?: Yes — full plan set, structural calcs, Title 24 energy compliance, and the LADBS back-and-forth so the homeowner only signs at the milestones.
Can I build an ADU in a hillside zone?: Usually yes, but Hillside Ordinance grading and access rules add design time. We've built in Silver Lake, Mt. Washington, Hollywood Hills, and the Palisades — geotech and shoring are part of the workflow.
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.

ADU 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 adu builder feasibility before you spend on drawings.

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