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Westside 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.

Westside permits move quickly when the parcel is clearly inside the city of LA or Santa Monica grid — both jurisdictions run ministerial ADU review under state law. The variables are Coastal Zone status (anything west of Lincoln Blvd in Venice / Marina Peninsula), and whether a soft-story or seismic ordinance applies to the existing structure.

Westside cost band — 2026

$95K – $180K all-in

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

Westside permit clock

8–12 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.

  1. City of LA parcels: LADBS ePlanLA portal, ministerial ADU review under LAMC §12.22-A,33.
  2. Santa Monica parcels: SMMC §9.31.300 — locally streamlined, similar 60-day clock as state law.
  3. Coastal Zone (Venice west of Lincoln, Marina Peninsula): Coastal Development Permit may be required.
  4. Mello Act applies to demolition or replacement of existing residential units in the Coastal Zone.

What moves the Westside number.

  • Westside labor and dump fees price 8–12% above LA County median.
  • Coastal Zone parcels often add $15–40k in CDP consultant + biology survey costs.
  • Santa Monica seismic retrofit pairing on a duplex can add $35–80k tied to the ADU permit cycle.
  • Tight street parking (Venice, Mar Vista) drives crane / pump days higher than Valley jobs.

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.
Do I need a Coastal Development Permit for a Westside ADU?
Only if the parcel is inside the Coastal Zone — generally west of Lincoln Blvd in Venice and the Marina Peninsula. Inland Westside parcels (most of Santa Monica, Brentwood, Mar Vista east of Lincoln) do not.
Can I build an ADU in Santa Monica's R1?
Yes. SMMC §9.31.300 mirrors state ADU law on R1, R2, and multifamily lots, with ministerial 60-day review once the submittal is complete.

More we build in Westside.

JADU Builder in nearby LA areas.

Got a Westside project in mind?

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

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