Garage Conversion ADU in Los Angeles - Plans, Permits & Build, One Fixed Price

ADU in Los Angeles, CA

An ADU in Los Angeles starts with a permit set that matches your exact parcel, because this city’s rules change block by block. We design, permit, and build accessory dwelling units under one contract at one written price, from rear-alley garage conversions in West Adams to hillside detached units above Studio City. Whether you’re weighing a Standard Plan ADU or a full custom design, call (971) 497-2402 and we’ll walk the property line with you before a single drawing begins.

Call (971) 497-2402

Why Los Angeles Homes Are Different

Los Angeles runs on a housing stock from another era. The 1920s California bungalows of Highland Park and the post-war stucco tract homes of the east San Fernando Valley share something useful: detached garages at the rear property line, often fed by alleys. That geometry turns a garage conversion into the fastest permitted ADU in the city. But the same era that gave Los Angeles its alleys also left raised foundations common in Silver Lake and Leimert Park, where enclosing a garage slab means a structural floor assessment before a wall goes up.

Terrain splits the city in two. Flatland parcels from Boyle Heights to Westchester move through permits on predictable timelines. Hillside lots in the Hollywood Hills or the Santa Monica Mountain foothills pull geotechnical reports, retaining walls, and steep-slope grading into the project, which can double soft costs before drywall is ordered. And a significant share of Bel Air, Laurel Canyon, and upper Eagle Rock sits in Very High Fire Hazard Severity Zones, where Chapter 7A ignition-resistant construction requirements add real dollars to the material list. A two-mile move downhill changes the entire budget.

Los Angeles is also Seismic Design Category D. Every new ADU foundation, including a simple garage conversion, requires an engineered shear-wall design. Homeowners who have seen simpler permits in lower-seismicity cities are often surprised by that line item. We plan for it from the first site assessment.

Our Main Los Angeles Services

The two projects Los Angeles homeowners call us about most are garage conversions and new detached units. Both fit the city’s alley-grid flatland lots, both fall under the same one-contract model, and both start with a written price.

Garage Conversion ADU in Los Angeles

The existing garage is already at the rear property line, already has a slab, and in most flatland Los Angeles neighborhoods it already sits inside the building envelope. That means no setback variance, the extra distance the city requires between your ADU and the property line. In West Adams, Boyle Heights, and Leimert Park, we regularly convert pre-1960 two-car garages into one-bedroom units with kitchens and full baths. The dominant question on older raised foundations is floor structure, not framing. Read the full breakdown here: Garage Conversion ADU in Los Angeles.

New Detached ADU in Los Angeles

A new detached ADU on a flat Los Angeles parcel is the cleanest build we do: the foundation is new, the shear-wall design is applied from the first stud, and the utility runs are planned, not retrofitted. On hillside parcels in the Hollywood Hills or the Santa Monica Mountain foothills, the same project gains a geotechnical report, grading plan, and often a retaining wall before framing starts. That work is predictable and documented line by line. See the full Los Angeles scope here: New Detached ADU in Los Angeles.

ADU Design & Permitting in Los Angeles

ADU Design & Permitting in Los Angeles is the phase where the city’s Standard Plan ADU Program meets reality. Los Angeles offers pre-approved architectural plans that skip full plan check, cutting months off the timeline on flatland parcels. But LADBS still requires a soils and grading clearance for hillside lots and a fire-zone determination before the permit counter accepts the application. A Valley parcel can look like a four-week permit; the same square footage above the flatland boundary in Fire Zone 4 can stall for months without someone who knows which clearance comes first. That is exactly the work our ADU Design & Permitting team does every week: the permit set as the core product, not an afterthought.

Site Assessment

Signs you need it

Your parcel is on a hillside, in a fire hazard zone, or has an existing foundation you plan to reuse, and you need to know what the city will actually accept before you spend money on drawings.

What it costs in Los Angeles

A site assessment in Los Angeles typically runs $650-$1,200, depending on hillside geotechnical requirements and fire-zone determination work.

How we do it

We measure the parcel, check the soils and grading clearance triggers, run the fire-zone determination, and document every finding in writing for the permit path ahead.

ADU Design & Blueprints

Signs you need it

You have a specific layout in mind that the pre-approved Standard Plans don’t fit, or your parcel has conditions the standard plans never anticipated.

What it costs in Los Angeles

Custom ADU design and blueprints in Los Angeles typically run $8,000-$15,000 for a flatland parcel, with hillside engineering adding from there.

How we do it

We draw the full permit set, coordinate structural and Title 24 energy compliance in the same document set, and hand you drawings that LADBS accepts without a designer-versus-builder gap.

What ADU Design & Permitting Costs in Los Angeles

Does the City of LA Standard Plan Program work on hillside lots?

Not automatically. The pre-approved plans bypass architectural plan check, but LADBS still requires a soils and grading clearance and a fire-zone determination on hillside parcels before the application is accepted. Call (971) 497-2402 for a parcel-specific read.

How long does ADU permitting take in Los Angeles?

Flatland Standard Plan ADUs can permit in weeks. Hillside or fire-zone parcels add geotechnical and Chapter 7A review that commonly stretches the timeline by months. We map the exact path in the site assessment, in writing.

Junior ADU & Interior Conversion in Los Angeles

Junior ADU & Interior Conversion in Los Angeles turns square footage you already own into rentable space without touching your setback. The city’s Rent Stabilization Ordinance exemption for new ADUs makes a JADU inside the footprint of your 1920s bungalow or 1950s stucco tract home a clean math problem. Our Junior ADU & Interior Conversion team works the interior path: no new foundation, no alley negotiation, just a permitted, documented conversion of space already under your roof.

Interior JADU

Signs you need it

You have an underused bedroom, den, or finished area with its own or easily added exterior access, and you want a permitted rental unit inside the existing home envelope.

What it costs in Los Angeles

An interior JADU in Los Angeles typically runs $70,000-$120,000, including the kitchenette, bath, and required separate entrance.

How we do it

We design the unit inside your existing walls, file the JADU permit set, and build the conversion under one contract with a written price before work starts.

Attached Addition ADU

Signs you need it

You want a larger attached ADU than a JADU allows, and your single-family home has the side or rear yard depth to extend the footprint.

What it costs in Los Angeles

An attached addition ADU in Los Angeles typically runs $180,000-$280,000, depending on foundation work and roofline tie-in complexity.

How we do it

We extend the existing foundation, frame the addition, run the utility connections from the main house, and deliver a permit set and finished unit as one contract.

What Junior ADU & Interior Conversion Costs in Los Angeles

Does a JADU in Los Angeles trigger parking requirements?

No. Junior ADUs are exempt from additional parking requirements under city policy, which is why they work so well on dense flatland lots with no room for a second car. Call (971) 497-2402 for a footprint check.

Can I rent a JADU separately from the main house?

Yes in most cases, and new ADUs in Los Angeles are explicitly exempt from the city’s Rent Stabilization Ordinance, so the rent you set at the start stays your number. We confirm this in the permit file.

ADU Site Prep & Utilities in Los Angeles

ADU Site Prep & Utilities in Los Angeles is where the ground under your parcel decides the budget. The city’s older neighborhoods pack decades of buried lines into narrow rear easements, and the seismic shear-wall mandate means every foundation starts with an engineered plan, not a standard pour. We handle the underground and the above-ground in one sequence: grading, foundation, panel, lateral, gas, and the hardscape that makes it look finished. Our ADU Site Prep & Utilities crew documents every visit with photos, so you see what was found under the slab, not a summary of how it felt.

Foundation & Grading

Signs you need it

You are building on a raised foundation home, a hillside parcel, or any site in Seismic Design Category D where an engineered shear-wall foundation is required.

What it costs in Los Angeles

Foundation and grading in Los Angeles typically runs $18,000-$40,000, with hillside parcels on the higher end due to geotechnical and retaining work.

How we do it

We run the soils check, dig and form the foundation per the engineered shear design, and document the pour with photos before the framing crew arrives.

Electrical Panel Upgrade

Signs you need it

Your existing panel is a 100-amp unit from the 1950s or 60s and cannot carry the new ADU’s load without tripping, or LADBS flags it during permit review.

What it costs in Los Angeles

A panel upgrade in Los Angeles typically runs $3,500-$7,500, depending on service size and whether the meter location moves.

How we do it

We replace the panel, run the new subpanel feed to the ADU, and pull the electrical permit as part of the same written scope, not as a change order.

What ADU Site Prep & Utilities Costs in Los Angeles

Does Los Angeles require fire sprinklers in every ADU?

No, but parcels in Very High Fire Hazard Severity Zones face Chapter 7A ignition-resistant requirements, and fire sprinklers are often the most straightforward path to compliance. Call (971) 497-2402 for a zone check on your parcel.

Will the site prep price change once excavation starts?

Not under our contract. The written scope locks at signing under Haven Standard Clause 5, and we photograph what we find underground so the price and the evidence match.

Brands We Service in Los Angeles

We specify and coordinate prefab and modular systems from Abodu, Cover, and Dvele within our Los Angeles projects, with the permit set and site work under the same contract. Parts and panel coordination run through our brands network, keeping delivery timelines tied to the drawings, not a separate vendor.

Pricing for ADU in Los Angeles, CA

Neighborhoods We Serve in Los Angeles

We work the full flatland-to-hillside range across Los Angeles, from alley-grid bungalow neighborhoods to fire-zone parcels in the foothills. Crews run daily routes across the east San Fernando Valley, the central flatlands, and the Hollywood Hills, with response times on estimates typically inside one business week.

• West Adams
• Boyle Heights
• Leimert Park
• Silver Lake
• Eagle Rock

Service Area - Cities Near Los Angeles

We also serve the flatland cities bordering Los Angeles to the east and south, where many of the same 1920s-1950s garage-heavy lots appear at a smaller scale. If you are in Huntington Park, CA, South Gate, CA, Bell, CA, or Maywood, CA, the same written-price, one-contract model applies.

FAQs About ADU in Los Angeles