Trusted New Detached ADU for Camarillo Homeowners
A Camarillo New Detached ADU typically costs between $285,000 and $525,000 all-in, from the first site survey through final inspection, depending on whether you choose a custom build or a prefab system. Ellery ADU Studio has designed, permitted, and built over 900 ADUs since 2015, the year California’s ADU laws began their major shift, and every project has started with a written price before any work began. If you’re a Camarillo homeowner who bought between 2015 and 2025 and you’re weighing an ADU as a long-term asset rather than a weekend project, we built this page for you.
We operate as a design-build studio, not a contractor who outsources drawings. The permit set, the construction documents, and the build itself live under one contract at one written price, which eliminates the designer-versus-builder blame gap that derails most ADU projects in Ventura County. Nadia Ellery leads the studio, and our license number appears on every page, verified, not just claimed. Call (805) 301-9518 to schedule your free estimate, or bring us any written estimate you already have for a Free Second Opinion.
What Our New Detached ADU Service Includes
Custom Built ADU
A custom built ADU is a site-constructed, stick-framed structure designed from foundation to finish to match your property’s specific constraints and your long-term goals. You need this approach when your Camarillo lot has unusual setbacks, significant grade changes, or neighborhood design guidelines that a prefab module cannot satisfy, which is common in the older estates near Camarillo Springs Golf Course and the hillside parcels above the 101. At Ellery ADU Studio, we produce the full permit set in-house, coordinate structural engineering for Camarillo’s specific seismic zone, and build to that same set, so the drawings and the finished structure are the same document, governed by one contract at one written price under Haven Standard, Clause 1.
Prefab ADU Installation
Prefab ADU installation brings a factory-built module to your Camarillo property, crane-set onto a prepared foundation, then finished and connected to utilities on-site. This path makes sense when your timeline is compressed or when you want cost predictability that site-built framing cannot guarantee, particularly for homeowners in the Pleasant Valley area who need rental income to offset a high 2018-2022 mortgage. We specify and coordinate prefab systems from Abodu, Cover, and other manufacturers within the same single contract, handling the Camarillo permit set, the foundation prep, the crane logistics, and the final utility tie-ins ourselves, so you do not manage separate vendors for design, delivery, and build.
Modular ADU
A modular ADU differs from standard prefab in that it is built to the California Building Code in factory-controlled conditions, then transported in sections and assembled on your Camarillo foundation as a permanent real estate improvement, not personal property. This is the right choice when you need a two-bedroom configuration or when your lender requires a structure that appraises as real property, which many Ventura County loan officers now demand for ADU financing. Ellery ADU Studio coordinates modular systems from Dvele, Mighty Buildings, and Plant Prefab, producing the site-specific permit set that the factory needs, then managing foundation, set, and finish as one scope with one written price locked at signing under Haven Standard, Clause 5 (No Surprises).
Studio ADU
A studio ADU is a single-room detached dwelling, typically 300 to 450 square feet, with a full bathroom and kitchenette, designed for rental income, home office use, or aging-in-place for a family member. In Camarillo, where many lots in the Mission Oaks and Las Posas Estates areas have the rear yard space but not the budget for a full one-bedroom, the studio format often pencils best for rental yield relative to construction cost. We design studio ADUs with the same permit-set rigor as larger units, including Title 24 energy calculations specific to Camarillo’s climate zone, and we build them under the same single contract with the same 365-Day Done Right Promise that backs every Ellery project.
1-Bed & 2-Bed ADU
A one-bedroom or two-bedroom detached ADU adds dedicated sleeping space, a separate living area, and full kitchen and bath facilities, typically ranging from 500 to 1,200 square feet depending on your Camarillo lot coverage and setback allowances. You need this format when the unit will house a tenant long-term, when you are building for adult children returning home, or when Ventura County rental market data shows that bedroom count drives monthly rent more than square footage alone. Our design-build process produces architectural drawings, structural calculations, MEP plans, and landscape integration documents as one permit set, then builds to that set at the written price quoted before any work started, with a documented photo record on every visit so you see what was found and what was done, not a summary of how it felt.
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
We specify and coordinate prefab and modular systems from Abodu, Cover, Dvele, Mighty Buildings, Boxabl, Plant Prefab, Tuff Shed, and James Hardie within the same single contract that covers design, permitting, and construction. With Tuff Shed, we have completed multiple studio and one-bedroom installations in Ventura County, coordinating their engineered wall panels with our site-specific foundation and utility connections to meet Camarillo’s wind-load requirements. For James Hardie fiber-cement siding systems, we specify their products as the exterior finish on both custom builds and prefab-coordinated projects, leveraging their 30-year warranty and our familiarity with their installation details to avoid the moisture-intrusion callbacks that plague less experienced crews.
Whether your project involves Abodu, Cover, Tuff Shed, James Hardie, or any other manufacturer, we can help. Our role is to translate their factory specifications into a Camarillo-permit-ready document set, then manage the site work that turns that module into a legal, inspected, habitable dwelling with a certificate of occupancy.
Signs You Need New Detached ADU Right Now
- Your mortgage payment has become unsustainable since your 2018-2022 purchase. Many Camarillo homeowners who bought at peak pricing are now carrying debt service that exceeds 40% of gross income. A permitted, income-producing ADU can offset $2,000-$3,500 monthly in Ventura County’s rental market, turning a liability into a performing asset. The longer you delay, the more interest you pay without rental income to offset it.
- You have aging parents who need proximity but independence. The cost of assisted living in Ventura County now exceeds $6,000 monthly. A studio or one-bedroom detached ADU on your Camarillo property provides family oversight without the institutional setting, and it preserves your home’s primary function. Zoning rules can change; building under current Camarillo ADU ordinances locks in your entitlement.
- Your adult children have returned home and need separate space. The “boomerang” demographic is largest in California’s high-cost metros, and Camarillo is no exception. A detached ADU preserves your household’s sanity while giving your children a mailing address and rental history that helps them eventually qualify for their own mortgage. Converting a garage or sharing the main house does not offer the same independence or resale value.
- You work from home and need dedicated, quiet space. The remote-work shift is permanent for many Ventura County professionals, and a studio ADU functions as a home office that qualifies for the home-office deduction while remaining convertible to rental use if your employment situation changes. Building it as a dwelling unit, not a shed, preserves your optionality.
- Your lot has unused rear yard space that is deteriorating or underutilized. Camarillo’s ADU ordinance allows detached units on most residential lots with sufficient setbacks, and leaving that space as dead lawn or storage generates zero return. Every year of delay is a year of lost depreciation, lost rental income, and potential entitlement changes that could restrict what you build.
Our New Detached ADU Process - Step by Step
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Site Survey and Feasibility Study. We visit your Camarillo property, measure setbacks to the property line, document existing utilities, and photograph conditions from multiple angles. You receive a documented photo record of what we found, not what we felt, including tree locations, slope grades, and utility access points that affect foundation type and cost.
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Written Price Before Any Work Starts. Within two weeks of the site survey, we deliver a line-item written quote covering design, permitting, and construction. This is not an estimate that shifts later. Under Haven Standard, Clause 1, the price is locked before any contract is signed, and under Clause 5, the scope is locked at signing with no door-side upsells and no scope creep.
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Permit Set Production and Submission. Our in-house designers produce architectural plans, structural calculations, Title 24 energy compliance, and MEP drawings as one integrated permit set. We submit to the City of Camarillo Community Development Department and manage plan-check corrections ourselves, so you do not coordinate between a separate designer and a separate permit expeditor.
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Construction and Documented Progress. Once permitted, our background-checked, uniformed crews execute the build to the approved drawings. Every site visit generates a documented photo record that you receive, showing what was found and what was done, from footing inspection through final walkthrough. The permit set is the build document; if the finished ADU is not built to the permitted drawings, our 365-Day Done Right Promise requires us to make it right, in writing, before the project starts.
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Final Inspection and Certificate of Occupancy. We schedule and pass all Camarillo inspections, including foundation, framing, insulation, mechanical, electrical, plumbing, and final. You receive the certificate of occupancy, the as-built documentation, and the full photo record, with the 365-Day Done Right Promise still in force. The unit is now a legal, income-producing dwelling on your property records.
How Much Does New Detached ADU Cost in Camarillo?
A typical studio ADU in Camarillo runs $285,000-$375,000 all-in, drawings through final inspection, per our New Detached ADU cost guide. A one-bedroom detached unit typically ranges from $340,000-$450,000, and a two-bedroom unit from $410,000-$525,000, depending on foundation type, utility extension distance, and finish level. Prefab and modular systems from Abodu or Cover often land in the lower half of these ranges for comparable square footage, while custom builds with complex grading or high-end finishes push toward the upper end.
| ADU Type | Typical Range in Camarillo | Primary Cost Drivers |
|---|---|---|
| Studio ADU (300-450 sq ft) | $285,000 - $375,000 | Foundation type, utility distance, prefab vs. custom |
| 1-Bedroom ADU (500-750 sq ft) | $340,000 - $450,000 | Kitchen specification, roof complexity, site access |
| 2-Bedroom ADU (750-1,200 sq ft) | $410,000 - $525,000 | Square footage, structural engineering, finish level |
| Prefab/Modular (varies by brand) | $260,000 - $420,000 | Module cost, crane access, site prep scope |
What moves the price: foundation conditions (expansive soils in parts of Camarillo require engineered footings), utility extension distance (sewer and water lines from the main house to a rear-yard ADU can exceed $15,000 on deep lots), and finish selections (appliance packages, flooring, and exterior cladding vary widely). What does not move the price: once you sign, the price is fixed under Haven Standard, Clause 5. No change orders unless you request a change in writing.
How to avoid overpaying: bring us any written estimate you already have for a Free Second Opinion. We will review the scope, identify missing line items that become surprise costs later, and confirm whether the permit set is included or outsourced. Many Camarillo homeowners have shown us estimates that omitted sewer lateral work or Title 24 compliance, which added $20,000-$40,000 after construction started.
What’s included in our free estimate: a site-specific feasibility assessment, a line-item written quote with every major cost category named, and a clear statement of what is not included (typically, your selection of finishes beyond our standard package, and any required geotechnical report if soils are suspect). Call (805) 301-9518 to schedule yours.
New Detached ADU Near Camarillo - Our Service Area
We design, permit, and build new detached ADUs throughout Ventura County and into western Los Angeles County, including New Detached ADU in Thousand Oaks, New Detached ADU in Moorpark, Westlake Village, Fillmore, Oak Park, Agoura Hills, Simi Valley, Malibu, Calabasas, West Hills, and Chatsworth. Most Camarillo properties are within 20 minutes of our project teams, and we maintain active permit submissions at the City of Camarillo, Ventura County, and the relevant LA County jurisdictions simultaneously. If you are unsure whether your property falls within our service area, call (805) 301-9518 and we will confirm your jurisdiction and typical response time on the same call.
Serving Camarillo, CA - Our Local Coverage Area
We’re based in the Camarillo area and know this community well. 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 Camarillo
A new detached ADU is a separate, self-contained dwelling built from the ground up on your property, not converted from an existing structure like a garage. It has its own foundation, walls, roof, kitchen, bathroom, and utility connections, and it is legally permitted as a second dwelling unit on a single-family lot. In Camarillo, detached ADUs are allowed on most residential-zoned lots with sufficient setbacks and lot coverage, and they offer the highest rental income and resale value of any ADU type. Call (805) 301-9518 for a free feasibility assessment of your specific lot.
From contract signing to certificate of occupancy, a typical new detached ADU in Camarillo takes 8 to 14 months, with 3 to 5 months for design and permitting and 5 to 9 months for construction. Prefab and modular systems from Abodu or Cover can compress the construction phase to 3 to 5 months, though permitting timelines remain similar. Delays usually come from plan-check revisions at the City of Camarillo, which we minimize by submitting a complete permit set the first time, or from utility coordination with Cal Water or Ventura County Sanitation, which we manage as part of our single-contract scope. Call (805) 301-9518 for a timeline specific to your property.
A new detached ADU in Camarillo typically costs between $285,000 and $525,000 all-in, depending on size, foundation type, and whether you choose custom construction or a prefab/modular system. For comparison, see our New Detached ADU in Thousand Oaks pricing. Studio units start near $285,000, one-bedroom units near $340,000, and two-bedroom units near $410,000, with high-end custom builds or difficult sites reaching the upper end of the range. Every Ellery project begins with a written price before any work starts, per Haven Standard, Clause 1, and that price is fixed at contract signing with no change orders unless you request a scope change in writing. Call (805) 301-9518 for your specific written quote, estimates are free.
Yes, we specify and coordinate Abodu, Cover, and other prefab and modular brands within the same single contract that covers your design, permitting, and site construction. We have active relationships with both manufacturers and understand their lead times, foundation requirements, and crane specifications, which vary by module size and your Camarillo site’s access constraints. Our role is to produce the site-specific permit set that Abodu or Cover needs, then manage foundation, utility, and finish work so you do not coordinate separate vendors. Call (805) 301-9518 to discuss whether a prefab system fits your timeline and budget.
A new detached ADU is planned construction, not an emergency service, so we do not offer same-day dispatch or 24/7 emergency response for new builds. What we do offer is a live person answering calls 24/7, no voicemail queue, no callback promise that does not materialize, so you can reach us when you are ready to discuss your project. For genuine emergencies on existing structures, such as storm damage or utility failure at an ADU already in use, we can assess whether our ADU Site Prep & Utilities team can respond. Call (805) 301-9518 at any hour to reach a live person.
Every new detached ADU is backed by our 365-Day Done Right Promise: if the finished ADU is not built to the permitted drawings, we make it right, and this promise is in writing before the project starts. Beyond that one-year workmanship guarantee, manufacturer warranties apply to specific components, James Hardie siding carries a 30-year product warranty, and structural elements are warranted per California contractor law. We also provide a documented photo record on every visit, so if a question arises later, we have evidence of what was found and what was done, not a summary of how it felt. Call (805) 301-9518 to review the full warranty documentation before you sign.
Gather your property’s assessor parcel number, any existing survey or plot plan you received at purchase, and a rough idea of your budget range and intended use, rental income, family housing, or home office. If you have a written estimate from another firm, bring it for our Free Second Opinion, we will identify missing scope items and verify whether the permit set is included or an additional cost. We will handle the site measurements, utility location, and setback verification ourselves during the feasibility visit. Call (805) 301-9518 to schedule, estimates are free and come with a written price before any work starts.
Schedule Your New Detached ADU Service in Camarillo Today
Call (805) 301-9518 to schedule your free estimate. A live person answers 24/7, no voicemail queue, and you will receive a written, line-item price before any work begins, guaranteed under Haven Standard, Clause 1. Bring any written estimate you already have for a Free Second Opinion. Nadia Ellery and the team at Ellery ADU Studio are ready to walk your Camarillo property, assess feasibility, and show you exactly what a new detached ADU will cost, what it will include, and how long it will take, with no urgency theatre and no surprises.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Camarillo since 2015.