Trusted New Detached ADU for Los Angeles Homeowners
A new detached ADU in Los Angeles typically costs $280,000 to $520,000 all-in, from first site measure through final inspection, and takes 10 to 16 months depending on hillside conditions, soil reports, and how quickly LADBS clears your permit set. That range is not a teaser. It’s the number we put in writing before you sign anything, per Haven Standard Clause 1. Ellery ADU Studio has designed, permitted, and built 900+ ADUs since 2015, the year California’s ADU permitting landscape shifted, and Nadia Ellery leads every project personally from feasibility through closeout. Call (971) 497-2402 to schedule a site walk. You’ll get a written price, not a ballpark.
We’re a design-build studio, not a contractor who subs out the drawings. The permit set, the structural engineering, and the construction live in one contract at one written price. That matters in Los Angeles, where a designer’s drawing and a builder’s interpretation can drift apart and leave you holding the correction. With our model, there is no designer to blame and no builder to chase. There is one name on the contract and one person accountable for it: Nadia Ellery.
What Our New Detached ADU Service Includes
Custom Built ADU
A custom built ADU is a ground-up structure designed to your lot, your setbacks, and your household’s actual use, whether that’s a rental, an office, or housing for parents. We don’t start with a stock plan and hope it fits. We start with a site survey, a soils check, and a zoning read specific to your Los Angeles neighborhood, then draw the structure to match what the city will approve. Every custom build includes a full permit set, a written scope, and a documented photo record on every visit, so you can see the foundation, framing, and rough-in as they actually happened.
Prefab ADU Installation
Prefab ADU installation means the structure is built in a factory and delivered to your site as panels or modules, then set and finished by our crew. In Los Angeles, prefab often shortens the on-site timeline by 8 to 14 weeks compared to stick framing, though the utility work and foundation remain the same. We specify and coordinate systems from brands like Abodu, Cover, and Dvele inside the same single contract, so the factory’s scope and our site scope don’t fight each other. The permit set still governs everything, and the 365-Day Done Right Promise still applies.
Modular ADU
A modular ADU is built in sections off-site, delivered on a truck, and craned into place, usually over two to five days. The trade-off in Los Angeles is crane access: narrow streets, overhead lines, and hillside lots can change delivery feasibility, so we confirm access before you commit to modular. We’ve coordinated modular builds from Mighty Buildings and other manufacturers, and we handle the foundation, utility connections, and finishes in the same contract. When modular works, it works well; when it doesn’t, we tell you on the first site visit, not after the deposit.
Studio ADU
A studio ADU is a single open living space with a kitchenette or full kitchen, one bathroom, and often a small mechanical closet, typically 350 to 500 square feet in Los Angeles. It’s the most requested configuration for rental income because it costs less to build and rents fast in neighborhoods like Highland Park, West Adams, and Huntington Park. We design studio ADUs to LADBS minimums without making them feel like minimum housing, and we price the full scope, drawings through final inspection, before work starts. For a 400-square-foot studio, expect the lower end of our cost range, though site conditions can move that number.
1-Bed & 2-Bed ADU
A one-bedroom or two-bedroom ADU is a separate house with enclosed bedrooms, a full kitchen, and more square footage, usually 550 to 1,000 square feet. In Los Angeles, these pencil out for homeowners who want long-term rental income or multi-generational housing, since the added bedroom increases rent and resale value without changing the lot line. We handle the full design-build: architectural drawings, structural engineering, Title 24 energy compliance, and construction under one written price. Two-bedroom ADUs often trigger additional parking or landscape requirements, and we flag those costs in the first written estimate rather than surprising you later.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Brands We Service for New Detached ADU
Abodu and Cover are the two factory systems we coordinate most often in Los Angeles, and we know their panel dimensions, foundation tolerances, and utility rough-in points well enough to spec the site work correctly the first time. With Abodu, the factory handles the shell and we handle foundation, utilities, and finish; with Cover, we work inside their panel system and coordinate the same scope. Neither one changes how we price: written price before work starts, one contract, one responsible party.
Dvele and James Hardie come up on our builds too. Dvele’s high-performance panels fit certain hillside and fire-zone lots where insulation and air sealing matter more, and we’ve coordinated their delivery on tight Los Angeles streets. James Hardie siding and trim products are a common specification on our custom and prefab projects alike, chosen because they hold up to coastal moisture and hold paint longer than wood. Whether your project uses one of these systems or stick framing from the foundation up, the process is the same: drawings first, written price second, construction third.
Signs You Need a New Detached ADU Right Now
- Your property taxes are high and your lot is underused. A 6,000-square-foot Los Angeles lot with a 30-foot backyard costs the same in property tax whether that yard produces income or not. A new detached ADU changes the math, and recent state law makes it easier to permit than it was before 2015.
- You’re renting out a garage with no heat and a bathroom that doesn’t meet code. That arrangement is a liability. A legal detached ADU rents for more, passes inspection, and doesn’t put you one tenant complaint away from a city citation.
- Your parents are aging and you don’t want them across the country. A detached ADU gives them their own door, their own kitchen, and their own address, while you stay 40 feet away. Los Angeles zoning now allows this on most single-family lots.
- You bought between 2015 and 2025 and your mortgage eats your margin. The ADU income offsets what you paid for the house. We see this constantly in neighborhoods like Atwater Village, Leimert Park, and North Hollywood, where purchase prices ran high and rent demand stayed strong.
- You’ve got a written estimate from another builder and it changed twice before the permit was pulled. Scope creep is not normal. Under Haven Standard Clause 5, our scope locks at signing, and the price doesn’t move unless you change the scope in writing.
Our New Detached ADU Process - Step by Step
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Site walk and feasibility read. Nadia Ellery walks your Los Angeles property, measures the setbacks, checks the access, and reviews the city’s zoning overlays for your specific address. Within a week, you get a written feasibility memo that says what can be built, what it will likely cost, and what permits are required. No charge for this first look.
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Written price and scope. You receive a line-item written price covering architectural drawings, structural engineering, Title 24, permit fees, and all construction. This is not an estimate that flexes. Under Haven Standard Clause 1, the price on the page is the price you pay. You review it, ask questions, and sign only when you’re ready.
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Permit set production. We draw the full permit set: site plan, floor plans, elevations, structural details, electrical, plumbing, mechanical, and energy compliance. The permit set is our core product, and we treat it that way. LADBS clears the drawings before we order a single board.
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Construction with a photo record. Our background-checked crew builds the ADU from foundation to final paint, and every visit ends with a documented photo record uploaded to your project file. You see the rebar before the pour, the framing before the drywall, and the rough-in before the close-up. Evidence, not summaries.
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Final inspection and 365-Day Done Right handoff. We walk the city inspector with you, close out the permit, and hand over your written warranty. If the finished ADU is not built to the permitted drawings, we make it right, in writing, within 365 days. That promise is the last line in your contract, not a sales phrase.
How Much Does a New Detached ADU Cost in Los Angeles?
A new detached ADU in Los Angeles typically runs $280,000 to $520,000. A 400-square-foot studio ADU on a flat lot with easy access lands closer to $280,000. A two-bedroom ADU with a hillside foundation, upgraded panel, and retaining work can reach $520,000. The gap between those numbers is site conditions, not builder margin.
What moves the price: soil tests and foundation type (slab versus pier and grade beam), sewer lateral depth, electrical service capacity, and whether your lot sits in a hillside or brush fire zone with additional requirements. What should not move the price: the builder changing the number after you sign. That’s why Haven Standard Clause 1 matters. The price is written before work starts, and the scope locks at signing under Clause 5. If you already have a written estimate from another Los Angeles builder, bring it in. We’ll give you a free second opinion on it, line by line, and tell you where the padding is.
New Detached ADU Near Los Angeles - Our Service Area
We build new detached ADUs throughout Los Angeles County, including Highland Park, Eagle Rock, Silver Lake, West Adams, Van Nuys, Northridge, Woodland Hills, and the South Bay. Most site walks are scheduled within 5 to 7 business days, and we plan construction around LADBS inspection timelines, not the other way around. If you’re comparing builders across Southern California, see how our process holds up against New Detached ADU in Houston and New Detached ADU in San Antonio. The cities differ; the written price guarantee does not.
Serving Los Angeles, CA - Our Local Coverage Area
We’re based in the Los Angeles area and know this community well, from South Gate to the westside. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions - New Detached ADU in Los Angeles
A new detached ADU is a separate residential unit built from the ground up on the same lot as your primary house, with its own entrance, kitchen, bathroom, and address. In Los Angeles, state and local law allows at least one detached ADU on most single-family residential lots, subject to height, setback, and lot coverage rules. Unlike a garage conversion, a detached ADU in Bell or anywhere in our service area starts with an empty site and a new foundation, which means you’re building exactly the floor plan you want instead of working around an existing structure.
Most new detached ADUs in Los Angeles take 10 to 16 months from the first site walk to final inspection. Permitting at LADBS runs 3 to 5 months depending on plan check volume and whether your lot requires discretionary review. Construction typically runs 6 to 9 months, with prefab and modular builds on the shorter end and custom hillside builds on the longer end. Call (971) 497-2402 and we’ll give you a timeline specific to your site.
A new detached ADU in Los Angeles costs $280,000 to $520,000 depending on size, foundation type, utility work, and finishing level. That price includes architectural drawings, structural engineering, Title 24 energy compliance, permit fees, and all construction labor and materials. The price you receive from Ellery ADU Studio is written, fixed, and backed by Haven Standard Clause 1, so the number you sign does not drift. Call (971) 497-2402 for a written quote specific to your lot.
We specify and coordinate prefab and modular systems from Abodu, Cover, Dvele, and other manufacturers inside our single design-build contract. That means the factory builds the panels or modules and our crew handles the foundation, utility connections, and finishes. The permitting, the written price, and the 365-Day Done Right Promise remain ours, so you have one accountable party for the entire job.
We don’t use urgency to sell, because a permit set can’t be rushed and a foundation can’t cure faster to make a deadline. What we do offer is a live person answering calls 24/7, including weekends, so you can schedule a site walk when you’re ready to move. If you’re working inside a window, like a lease ending or family arriving, tell us on the first call and we’ll sequence the project around the dates that matter.
Every Ellery ADU Studio project includes a 365-Day Done Right Promise in writing: if the finished ADU is not built to the permitted drawings, we make it right. We also include a written workmanship warranty, and we document every construction visit with photos so warranty conversations are about evidence, not memory. Before the project starts, you’ll have the warranty language in your contract, not a verbal assurance.
Have your property address, a copy of any recent survey or title report if you have one, and any written estimates from other Los Angeles builders ready for review. We’ll measure setbacks, check access for equipment and delivery, and talk through your intended use for the ADU, since a rental, an office, and a parent suite lead to different floor plans. You don’t need to clear brush or move anything. We document what we find and put the findings in writing.
Schedule Your New Detached ADU Service in Los Angeles Today
If you’re weighing a new detached ADU in Los Angeles, the next step is a site walk and a written price. No phone-tag estimates, no designer-versus-builder finger-pointing, no number that changes after signing. Call (971) 497-2402 and you’ll reach a live person who can schedule your walk and answer questions about permits, pricing, and timeline. The first look costs nothing. The written price is yours to keep.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Los Angeles since 2015.