New Detached ADU in Los Angeles - Design, Permits and Build Under One Contract

Fast, Reliable New Detached ADU Across Los Angeles

A new detached ADU in Los Angeles typically runs $220,000-$450,000 all-in, from permit set through final inspection, depending on whether your lot qualifies for the city’s Standard Plan Program or requires full custom engineering. We’re Nadia Ellery’s team at Ellery ADU Studio, and we’ve designed, permitted, and built over 900 ADUs since 2015 - the year California’s ADU laws shifted. Our Los Angeles office coordinates dispatch and scheduling locally; crews serve neighborhoods from the San Fernando Valley to Mid-City without the delays of out-of-market contractors who don’t know LADBS’s inspection routes. Call (747) 322-4648 to schedule your free estimate.

Call (747) 322-4648

Why Ellery ADU Studio Burbank Is Los Angeles’s Preferred New Detached ADU Company

We’ve built our reputation in Los Angeles on one thing: every project gets a written price before any work starts, per Haven Standard Clause 1. No “call for a quote.” No ballpark that balloons. Homeowners in Silver Lake, Tarzana, and Highland Park come to us after they’ve already talked to contractors who couldn’t explain why their bid jumped $40,000 after demolition.

Our reviews from Los Angeles clients consistently cite the documented photo record we deliver on every visit - not a summary of how work “felt,” but timestamped evidence of what we found and what we did. A live person answers our phones 24/7. When a hillside lot in the Valley triggers the Hillside Ordinance or a Mid-City flat-zone job sails through on Standard Plans, we know the difference because we’ve navigated both. That’s local expertise you can’t fake.

Our New Detached ADU Services in Los Angeles

Custom Built ADU

Custom built ADUs in Los Angeles are the only path for roughly a third of residential parcels - those in Very High Fire Hazard Severity Zones or on slopes over 15% where the Hillside Ordinance voids pre-approved plans. We engineer caisson or grade-beam foundations for expansive clay soils and Seismic Design Category D, specify Chapter 7A ignition-resistant construction, and pull full structural and MEP permits through LADBS. A typical custom detached ADU in Los Angeles runs $320,000-$450,000 all-in.

Prefab ADU Installation

Prefab ADU installation in Los Angeles works best on flat-zone lots with clear access for crane sets - think the grid-like streets of Crenshaw or the wide alleys of the Valley’s postwar tracts. We specify and coordinate Abodu, Cover, and Mighty Buildings systems within our single-contract model, meaning the manufacturer’s drawings integrate directly into our permit set. No designer-versus-builder blame gap. Prefab detached units in Los Angeles typically run $220,000-$340,000 installed, including foundation and utility tie-ins.

Modular ADU

Modular ADUs in Los Angeles follow the same flat-zone advantage as prefab, with the added benefit of volumetric construction completed in-factory. We coordinate Dvele and Plant Prefab modules through our design-build contract, handling transport permits for oversized loads on LA’s restricted truck routes and crane placement on tight 5,000 sq ft R1 lots. Modular detached ADUs in Los Angeles generally fall between $260,000-$380,000.

Studio ADU & 1-Bed & 2-Bed ADU

Studio ADUs and 1-bed & 2-bed ADUs in Los Angeles dominate the Standard Plan Program - pre-approved footprints that bypass weeks of plan check. But here’s the catch: the moment your lot triggers the Hillside Ordinance, those plans are void. We verify slope, fire zone, and utility capacity before quoting. A studio detached ADU in Los Angeles runs $220,000-$290,000; 1-bed units $260,000-$340,000; 2-bed units $300,000-$420,000. Every range is written and locked at signing under Haven Standard Clause 5 (No Surprises).

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Trusted Brands We Service in Los Angeles

We specify and coordinate prefab and modular systems from Abodu, Cover, Mighty Buildings, Dvele, and Plant Prefab - all within our single-contract design-build model. Our Los Angeles office maintains relationships with these manufacturers’ West Coast logistics teams, which means faster lead times on panel deliveries and direct escalation when a module spec conflicts with LADBS’s local amendments. We don’t resell kits. We integrate them into a permit set that we stand behind through final inspection.

Common New Detached ADU Problems We See in Los Angeles Homes

• Existing garage slabs and framing never engineered for habitable loads. On 1940s Valley lots especially, the original two-car garage was built for vehicle weight, not residential code. Once LADBS requires the structural inspection at permit, we often find we need a full grade-beam or caisson foundation redesign - not a slab extension. We build this possibility into our contracts as a pre-negotiated allowance.
• Standard Plan Program eligibility killed by hidden slope. A lot surveyed as “flat” on ZIMAS can still trigger the Hillside Ordinance at 15.1% slope. Out-of-market contractors miss this constantly. We verify topography against LADBS’s slope calculation before quoting, because a voided Standard Plan means starting over with custom engineering and Chapter 7A detailing.
• Primary house utility deficiencies exposed by ADU permit. The new detached ADU shares your main panel and water service. When LADBS inspects, any knob-and-tube branch wiring, aluminum conductors, or failed waterproofing behind existing showers must be corrected before final. Our LA bids always carry pre-negotiated allowances for panel upgrades, re-piping, and seismic retrofit - priced in writing before demolition, not discovered after.
• Very High Fire Hazard Severity Zone construction requirements overlooked. Tarzana, Topanga-adjacent areas, and hillside pockets of Silver Lake require Chapter 7A ignition-resistant siding, ember-resistant vents, and Class A roofing. These aren’t upgrades. They’re code minimums that out-of-market contractors often omit from initial quotes, then discover at plan check.

Pricing for New Detached ADU in Los Angeles, CA

We Also Serve Cities Near Los Angeles

Our crews work throughout the metro core and adjacent municipalities. We regularly pull permits and coordinate inspections for New Detached ADU in Los Angeles clients in Culver City, Alhambra, West Hollywood, and Beverly Hills - each with their own building departments, amendment schedules, and inspection quirks that out-of-market contractors learn the hard way.

FAQs - New Detached ADU in Los Angeles