New Detached ADU in Los Angeles - One Fixed Price, Permits Handled

Fast, Reliable New Detached ADU Across Los Angeles

A new detached ADU in Los Angeles typically runs $220,000-$420,000 all-in, from permit set through final inspection, depending on whether you’re building on an alley-loaded flatland lot or an open site with grading and drainage work. Most projects take 8-14 months from signed contract to certificate of occupancy, with LADBS permit review currently averaging 12-16 weeks for standard plans and 6-10 weeks for pre-approved designs. Call (424) 523-8492 to schedule your free estimate - every quote is written, line-itemed, and locked before any work begins.

Call (424) 523-8492

We coordinate dispatch and scheduling from our Los Angeles office, and our crews work the full basin - from the Valley floor to the Eastside flatlands to the South LA grid. Los Angeles isn’t uniform. A detached ADU off Venice Boulevard in Culver City faces different utility routing, setback rules, and inspection sequences than one on an alley lot in Van Nuys or a hillside parcel in Glassell Park. We’ve designed, permitted, and built over 900 ADUs since 2015, and the ones that stay on schedule share one trait: the builder scoped the real site conditions before quoting, not after breaking ground.

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

Our reputation in Los Angeles rests on documentation, not declarations. Every client receives a written price before work starts - Haven Standard, Clause 1 - plus a documented photo record on every site visit and a 365-Day Done Right Promise backed in writing. We’ve completed ADU projects across Los Angeles, from prefab installations in West Adams to custom builds in Highland Park to modular units in the Crenshaw district. Our license number appears on every page, and our crews are background-checked and uniformed.

Response time matters when you’re holding a signed estimate from another builder and something feels off. We answer calls live, 24/7 - no voicemail queue, no callback that doesn’t materialize. If you have a written estimate in hand, we’ll provide a Free Second Opinion, line by line. We’ve caught $40,000-$80,000 scope gaps in competitor quotes, usually around alley utility routing, slab replacement, or panel upgrades that were assumed but not specified.

Local knowledge here means knowing LADBS’s permit portal, the Standard Plan Program, and the inspection backlog - not just carpentry. Los Angeles processes more ADU permits annually than any U.S. city, and the builders who thrive are the ones who treat the permit set as the core product, not an afterthought. That’s been our model since 2015.

Our New Detached ADU Services in Los Angeles

Custom Built ADU

Custom built ADUs in Los Angeles range from $260,000-$420,000, depending on square footage, finish level, and site complexity. We design and permit in-house, then build under the same contract at the same written price - no designer-versus-builder blame gap. On alley lots from Van Nuys to Watts, we specify shell materials that can be stick-built on site when crane access is impossible. We used a James Hardie-clad custom shell for a 640 sq ft studio off Gilmore Street in Van Nuys because the alley approach couldn’t accommodate a prefab lift over DWP power lines. Every custom build includes full structural engineering for seismic, Title 24 energy compliance, and the documented photo record required by Haven Standard Clause 3.

Prefab ADU Installation

Prefab ADU installation in Los Angeles runs $220,000-$340,000 for a complete project, though site conditions often push the final number. We specify and coordinate Abodu, Cover, and other panelized systems within our single-contract model. Prefab works beautifully on open lots with street access and crane clearance. It fails on alley lots with low power lines, tight turning radii, or no staging area. We scope crane path, truck access, and set-day logistics before quoting - not after the unit arrives. If your Los Angeles lot can’t take a crane lift, we’ll tell you in the first meeting and pivot to stick-built or modular alternatives.

Modular ADU

Modular ADUs in Los Angeles typically cost $240,000-$380,000, with Dvele and other factory-built systems available through our specification service. Modular differs from prefab in factory completion level - often 80-90% finished before delivery - which compresses on-site schedule but demands even tighter site logistics. Los Angeles’s narrow hillside streets and alley-loaded flatlands both present challenges. We verify truck route, crane or forklift set, and LADBS modular approval status before any deposit. The factory warranty and our 365-Day Done Right Promise run in parallel, not in conflict.

Studio ADU

Studio ADUs in Los Angeles - 300-450 sq ft, kitchenette and full bath - run $220,000-$320,000. These are the most common detached ADU we build on alley lots, where the existing one-car garage footprint limits expansion without variance. A studio ADU on an unreinforced slab in the Valley typically requires full slab replacement, shear walls with hold-downs, and alley-fed utility connections. We bundle this into the written quote upfront. No surprises at framing.

1-Bed & 2-Bed ADU

One-bedroom detached ADUs in Los Angeles range $280,000-$380,000; two-bedroom units run $340,000-$420,000. Bedroom count drives septic or sewer capacity, parking requirements under LADBS rules, and Title 24 mechanical load calculations. On open lots with county rather than city jurisdiction, septic setbacks and well clearances add planning complexity we scope before quoting. A 2-bed unit on acreage in the county islands east of the 110 needs perc testing, leach field design, and potentially a separate septic tank - none of which appear in a city-permit quote copied from LADBS.

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Trusted Brands We Service in Los Angeles

We specify and coordinate prefab and modular systems from Abodu, Cover, Dvele, Mighty Buildings, Boxabl, Plant Prefab, Tuff Shed, and James Hardie - all within our single-contract, single-written-price model. In Los Angeles, brand selection follows site conditions, not marketing brochures. James Hardie fiber-cement cladding performs well in our mild Mediterranean climate and meets the fire-resistance requirements increasingly common in hillside zones. Abodu and Cover units work where crane access and street frontage allow. We don’t push brands. We specify what fits your lot, your budget, and your permit path - then coordinate delivery, set, finish, and inspection under the same contract.

Common New Detached ADU Problems We See in Los Angeles Homes

• Alley utility routing assumptions. Scoping a detached ADU as a garage conversion without confirming the alley-side sewer lateral and DWP service path - street-frontage assumptions blow up the MEP scope after framing starts. We verify Bureau of Sanitation and LADWP inspection protocols before quoting.
• Unreinforced garage slabs. 1940s-1970s garage slabs across the Valley and South LA flatlands are commonly non-reinforced and undersized. A full slab and footing replacement, plus shear wall and hold-down engineering, gets bundled into our quote - not change-ordered later.
• Undersized electrical panels. Most post-WWII Los Angeles homes still carry original 100-amp or even 60-amp service. A detached ADU with electric heat, water heater, and appliances needs 200-amp service minimum. Panel upgrade is a separate LADWP coordination with its own timeline.
• Grading and drainage on open lots. Alleys and flat grid parcels shed water toward the ADU pad. No lot-wide drainage plan means the new detached structure sits in a pond at the first winter storm. We scope swale, French drain, or surface grading requirements before breaking ground.

Pricing for New Detached ADU in Los Angeles, CA

We Also Serve Cities Near Los Angeles

Our crews work throughout the Los Angeles basin and adjacent municipalities. We regularly build New Detached ADU in Los Angeles and in Culver City, West Hollywood, Beverly Hills, and Glendale - each with its own permitting authority, inspection protocols, and utility coordination requirements. County islands between city boundaries add septic, well, and grading variables that city-permit contractors often miss. We scope jurisdiction before quoting.

FAQs - New Detached ADU in Los Angeles