Full-Service ADU Builder in California – Design • Permit • Build
Let’s Build Your ADU Your Way!
Ready to turn that ADU dream into reality? Whether you’re looking to design a Custom ADU or want to fast-track things with a ready-to-build plan, we’ve got options that fit your style, timeline, and budget.
Custom ADUs
Custom ADUs
Build-Ready ADUs
Build-Ready ADUs
Our completed ADU projects
Addition to a Senior Living Facility
Lynnwood
- Size: 120 units
- No of stories: 3
- Special Features: Addition to a ground up senior living facility with 120 units & cottage homes
Albany ADU
Albany, CA
- Size: 800 sq ft
- No of stories: 2
- Special features: ADU with ~200 sq ft patio with wood trellis
Amburose Custom Home
Fremont
- Size: 2,984 sq ft
- No. of stories: 2
- Special features: Grand Entry with Stone Accents
Arcilla ADU
San Diego
- Size: 375 sq. ft
- No of stories: 1
- Special features: Compact design and skylight
Camden ADU
Oakland
- Size: 222 sq. ft
- No of stories: 1
- Special features: Compact design & murphy bed
Castro Valley ADU & Office/Gym Space
Castro Valley, CA
- Size: 798 sq ft ADU + 639 sq ft attached office/gym space
- No of stories: 1
- Special features: Attached office/gym space & newly completed driveway
Custom Home
Santa Rosa
- Size: 3,512 sq ft
- No of stories: 2
- Special features: Modern farmhouse design
Flying Lady Winery
St. Helena
- Size: 40,305 Sq. ft.
- No of stories: 1
- Special Features: A 2 story residence accompanied by a winery building, featuring an outdoor tasting deck.
Gallegos ADU
Watsonville
- Size: 750 sq ft
- Number of stories : 1
- Special features: Exterior deck & front porch
Governor ADU
Harbor City
- Size: 704 sq ft
- No of stories: 1
- Special features: ADA Accessibility
Millbrook Residence
Santa Rosa
- Size: 3416 sq ft
- No. of stories: 2
- Special features: Modern farmhouse-style custom home
Milpitas ADU
Milpitas
- Size: 800 sq ft
- No of stories: 2
- Special Features: 2-story unit designed to maximize living space with private entry, open living, and full-home functionality.
Modern Custom Home
Santa Rosa
- Size: 4,444 sq ft
- No of stories: 2
- Special features: Symmetrical modern farmhouse with grand entry and high ceilings
Multi Family Development
Location: San Diego
- Size: 18 units
- No of stories: 4
- Special Features: Ground up 18 unit multifamily development
Paxton custom home
Santa Rosa
- Size: 2,683 sq ft
- No of stories: 2
- Special features: Modern 2-story home with pool, spa and stone facade
Perlita ADU
Los Angeles
- Size: 1,200 sq ft
- Number of stories : 2
- Special features: Roof deck
Phan ADU
San Leandro
- Size: 750 sq ft
- No of stories: 1
- Special features: Designed for flexibility
Salvator Apartments
Sacramento
- Size: 120 units
- No. of stories: 4
- Special Features: Developed comprehensive steel shop drawings for the ground-up, four-story apartment complex
Sawgrass Residence
Santa Rosa
- Size: 3,100 sq ft
- No of stories: 1
- Special features: Vaulted beam ceilings & open layout
Shaff ADU
Aptos
- Size: 685 sq ft
- No of stories: 2
- Special features: 2 Car garage
Sierra Home
Sacramento
- Size: 4,084 sq ft
- No of stories: 1
- Special features: Mediterranean-inspired home with pool
Smiley custom home
Olympic Valley
- Size: 3,529 sq ft
- No of stories: 2
- Special features: Modern architecture with high ceilings
St. Leo’s Apartments
Redwood
- Size: 15 units
- No. of stories: 3
- Special Features: Ground-up construction, 3-story wood structure consisting of 15 units
Tynan Village Apartments
Salinas
- Size: 171 units
- No of stories: 4
- Stucco/construction work on the most recent project remodeling
Whittier ADU
Whittier
- Size: 700 sq ft
- No of stories: 1
- Special features: Custom built design
Custom ADUs: Perfect Fit for Your Home & Lifestyle
Build Ready ADU Plans
- 1188
- 3
- 2
- 650
- 2
- 1.5
- 420
- 1
- 1
What’s an Accessory Dwelling Unit (ADU)?
Think of an ADU as your property’s hidden gem.
Also known as a granny flat, in law suite, or backyard cottage, an ADU is a private, self-contained mini-home built right on your lot. It includes its own kitchen, bathroom, and entrance perfect for hosting guests, housing family, or earning rental income.
And here’s the best part: California & Washington laws now make it easier than ever to build one. Whether you’re looking to add space, boost property value, or generate income, an ADU is a smart, flexible solution. Let’s make it happen!
Types Of ADUs
1. Attached ADUs
2. Detached ADUs
Stand-alone structures located on the same lot as the primary home. These units are fully independent and offer complete privacy. Examples include one story or two story backyard cottages, studio units, casitas, or converted outbuildings. Detached ADUs are ideal for homeowners who want to maximize space without altering the existing home. They offer added privacy and are a great option for generating rental income.
3. Interior ADU
Created by converting a part of the existing home into a separate living space. These can include basements, attics or even an entire floor. Interior ADUs are a great way to utilize underused space within the home while maintaining the property’s original footprint.
4. Garage Conversion
ADU Benefits
More space
More space
Higher property value
Higher property value
Passive rental income
Passive rental income
Home for Loved Ones
Home for Loved Ones
Our Step by Step Approach
1,000+ Happy Customers.
Real Stories, Real Results.
Yelp Reviews
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After speaking with several construction companies on getting a permitted ADU built at a property, Urbatect seemed to be the most organized and reasonable in terms of timeline, quality, and... read more 
Nico W.
3/26/2025 I worked with Urbatech to plan the construction of an detached ADU in the backyard of my home. I had contacted several ADU construction companies to discuss the process... read more Ronald S.
11/27/2024 Worked with Urbatect Development to build an ADU in backyard. They worked with us getting the price we wanted as well as including upgrades that were deal breakers for us.... read more Brian S.
10/15/2024 - I was in a panic. I have been trying for 5 months to simply put in a window through hcd because I have a manufactured home. Endless delays. After being... read more Dori R.
10/05/2024 We are very satisfied with the work that Urbatect has provided us. We have worked together on several engineering projects and the team has always provided us with a superior... read more Joe P.
9/17/2024 Amazing service, excellent quality on design , for sure they will be my engineers for all my projects.
I highly recommend them. Lizzeth B.
9/12/2024 - Although there was some variability in the people I worked with as a client to Urbatect, I'm going to focus my evaluation on the outstanding engineer I worked with, Jay.... read more Gary O.
7/26/2024
The Urbatect Advantage
- 1. One-stop Solution With Expert Project Management, Design, Permit & Construction Team.
- 2. Flexible And Customizable Design-build Solutions With Allowances To Choose Your Own Finishes.
- 3. Budget Transparency & Cost Control With Fixed Pricing That Protects Against Labor And Material Cost Increases For 16 Months.
- 4. 25–30% Faster Project Completion Without Compromising Quality.
- 5. Dedicated Permit Technician & 30% Faster Permit Expediting.
- 6. Advanced Technology & 3D Visualization.
Call Us Now!
(669) 201-0805
Email Us
Contact@urbatect.com
Book an Appointment
Schedule a free consultation
What Sets Us Apart
Licensed
& Insured
FAQs
1. How long does it take to build an ADU?
The full process of designing, permitting, and constructing a new accessory dwelling unit (ADU) typically takes 10 to 16 months, depending on the complexity of your project, city processing times, and coordination with you throughout each phase. Here’s a general breakdown:
● Design & Permitting: 2 to 4 months
This typically includes concept plans, schematic and design development, and Title 24 compliance. Multiple design meetings and revisions are typically included during this phase to ensure your vision is fully incorporated in the design.
● Permitting: 3 to 4 months
Once plans are submitted, the city reviews them in plan check cycles. Timelines vary by jurisdiction and can depend on the city’s backlog as well, and may include revisions to the plans based on city feedback before final permit issuance.
● Construction: 5 to 8 months
Construction duration typically depends on unit size, complexity, site conditions, and city inspection timelines. This includes everything from site prep and framing to MEP installation, finishes, and the final Certificate of Occupancy.
We aim to complete ADU projects in 10 to 12 months whenever feasible, but always advise planning for up to 16 months to account for external delays.
2. What is the maximum size of the ADU I can build?
In California, the maximum size of your ADU depends on whether it’s attached or detached, your lot size, and your local city or county’s zoning regulations.
- Detached ADUs are allowed up to 1,200 sq. ft. in many areas, but state law requires all jurisdictions to permit at least 800 sq. ft., regardless of lot coverage, setbacks, or floor area ratio limits.
- Attached ADUs can typically be up to 50% of the size of your primary home, but must be allowed at least 800 sq. ft., even if 50% would be less.
Local ordinances may allow more but cannot restrict you below these state minimums. Every property is unique and may have specific conditions such as lot configuration, easements, setbacks, or local overlays that impact the maximum ADU size.
We offer a free property-specific assessment as part of our initial process even before a contract is signed to help define your scope and guide you clearly. Contact us at (559) 412-8841 or info@urbatect.com, and we’ll assess your site to confirm the maximum ADU size allowed under your city’s rules.
3. Why build an ADU as an investment?
Adding an ADU is not just a smart way to maximize your property it’s a long-term investment that boosts value, generates income, and offers greater flexibility for your evolving needs. Here’s why building an ADU makes strong financial sense:
- Boosts overall property value
- Builds equity immediately by adding livable square footage and a permitted unit to your asset
- Strong return on investment (ROI) in both resale and rental markets
- Generates passive rental income – short- or long-term
- Offers flexibility for future use (guest house, home office, aging parents, etc.)
- Provides private space for family or visitors
- More cost-effective than buying a new property or undertaking major home additions
- Adds diversification to your real estate investment portfolio
- Supports sustainable living with compact, energy-efficient design options
4. Do I have to live on the property to rent out my ADU?
No owner-occupancy requirements have been eliminated for ADUs across California, with the exception of Junior ADUs (JADUs). This means you’re not required to live on the property to rent out your ADU. However, JADUs still require the property owner to reside on-site, either in the main home or the JADU.
5. Are pre-approved ADU plans faster and more affordable?
Not necessarily. While pre-approved plans can be faster to permit, they still need to meet your specific site conditions and local city regulations, which can result in costly changes or delays if they don’t align perfectly. At Urbatect, we specialize in custom solutions that are designed to minimize revisions, avoid surprises, and ensure smoother permitting helping you save time and money in the long run.