Los Angeles Advanced ADU Builders
Los Angeles Advanced ADU Builders offers code-compliant ADU design, garage conversions (which account for 26% of new ADUs in LA, according to the California Department of Housing), and backyard additions, providing full project management throughout Los Angeles. We specialize in end-to-end planning, permits, and construction for residential accessory units.
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Why LA Homeowners Rely on Our ADU Solutions
Across Los Angeles, homeowners choose us for code-compliant, stress-free ADU projects. With 500+ completed builds and a 95% satisfaction rate, based on our 2023 post-construction survey, we deliver full-service design, permitting, and construction for modular ADUs, garage conversions, and JADUs. We also do detached new construction ADUs, modular and prefab ADU installations, and ADU remodeling to modernize existing spaces. As a local business, we know how to navigate LA’s complex zoning ordinances, SB 9, and SB 13 regulations. At Los Angeles Advanced ADU, you get peace of mind from a team committed to excellence in every project handled.
Start your custom ADU journey with a trusted local contractor—Los Angeles Advanced ADU.
Our Full-Service ADU Solutions in Los Angeles
We deliver complete ADU services in Los Angeles, including remodeling, structural upgrades, and finishes. Each ADU project is custom-planned to your lot and completed with code-compliant framing, roofing, and interior finish work.
Custom ADU Architectural Design
Custom ADU architectural design defines the structure, layout, and dimensions of your ADU. This service is performed at the planning phase to comply with LADBS and CRC requirements. Our site-specific plans help homeowners avoid revision delays and optimize space efficiency.
ADU 3D Renderings and Project Visualization
Our 3D rendering service visualizes your ADU design before construction using SketchUp and Revit. It helps 90% of clients finalize finishes, floor plans, and layouts earlier in the build timeline, reducing post-build revisions.
ADU Permit Application and Processing
We manage your full ADU permit process, including architectural documents, Title 24 compliance, and structural reports. Documents are submitted directly to LADBS and reviewed by plan evaluators. This service saves homeowners 6–8 weeks of potential delays during the permitting phase.
ADU Zoning and Code Compliance Assistance
We align your ADU plan with LAMC zoning laws and statewide rules like SB 9 and SB 13. This step prevents rejections in HPOZ or Hillside zones. Our zoning review avoids plan changes after submission, saving you time and resources.
ADU Site Evaluation
Before any construction work, we'll assess the site to ensure there are proper setbacks, utility access, and sewer line locations. We use Los Angeles County Assessor maps and Department of Water and Power (LADWP) data for proper evaluation. 70% of plan rejections are due to site limitations. That's why we do a thorough ADU Site Evaluation before the design and permitting phases. It's a crucial step you should never miss, especially in garage conversions and detached ADU construction. It gives you an early insight into the ADU's feasibility, so you can avoid additional costs and delays down the line.
Structural Engineering for ADU Construction
Structural engineering for ADU construction ensures that your accessory dwelling unit is safe, stable, and compliant with local building codes. This service is essential during the design and permitting phases to verify the integrity of foundations, framing, and load-bearing elements. Homeowners benefit from long-term safety and a streamlined approval process.
Garage Conversion ADUs
Garage conversion ADUs transform existing garages into fully functional living spaces, ideal for rentals or extended family. This service is applied during home renovations and requires careful planning for utilities and code compliance. Homeowners save on construction costs and make use of underutilized space.
Basement ADU Conversions
Basement ADU conversions repurpose your basement into a legal, comfortable dwelling unit. This service is typically performed during home remodeling projects and addresses challenges like moisture control and egress requirements. Homeowners gain extra living space and potential rental income without expanding their home’s footprint.
Above-Garage ADUs
Above-garage ADUs involve constructing a new living unit above your existing garage, maximizing vertical space. This service is ideal for properties with limited lot size and is integrated during new builds or major renovations. Homeowners benefit from increased privacy for tenants and efficient use of their property.
Junior ADU Construction
ADU space optimization and layout planning focuses on making the most of your available square footage to create functional and comfortable living areas. This service is typically applied during the early design phase to maximize usability and storage. Homeowners enjoy improved livability and higher property value.
Modular ADU Installation
Modular ADU installation delivers pre-built, factory-manufactured units that are assembled on your property. This service is typically applied for faster project timelines and predictable costs, with modules installed after site preparation. Homeowners benefit from reduced construction time and minimized site disturbance.
Prefab ADU Setup
Prefab ADU setup involves the delivery and installation of pre-fabricated accessory dwelling units designed for quick assembly. This service is used when homeowners want a turnkey solution with consistent quality and shorter build times. Benefits include lower labor costs and rapid occupancy.
ADU Space Optimization and Layout Planning
ADU space optimization and layout planning focuses on making the most of your available square footage to create functional and comfortable living areas. This service is typically applied during the early design phase to maximize usability and storage. Homeowners enjoy improved livability and higher property value.
Detached ADU Construction
Detached ADU construction involves building a separate, stand-alone dwelling unit on your property. This service is ideal for homeowners seeking privacy or rental income, and is performed from site preparation through final inspection. Detached ADUs offer flexible living arrangements and can increase your property’s versatility.
Attached ADU Construction
Attached ADU construction adds a new living space directly connected to your existing home, sharing at least one wall. This service is typically chosen during home expansions or remodels and follows local zoning and building regulations. Homeowners benefit from increased square footage and seamless integration with the main house.
Types of ADUs We Build
We build 13 types of ADUs in Los Angeles, including garage conversions, detached backyard units, modular homes, and second-story additions—all tailored for comfort, code compliance, and long-term value.
| Detached Backyard ADUs | A separate living unit built in your backyard—typically up to 1,200 square feet per Los Angeles regulations. It’s ideal for rental income, multigenerational living, or guest accommodations. |
|---|---|
| Attached Room Additions | This ADU is constructed as an extension to your existing home. Ranging from 400 to 1,200 square feet, it offers extra living space with direct access to the main building. |
| Garage-to-Living Conversions | Converted garages range from 200 to 400 square feet in size. It's a legal living space, perfect for creating an independent rental or in-law suite. |
| Junior ADUs (JADUs) | A 500 sq. ft. unit built within your home. Includes a kitchenette and separate entry—perfect for students, relatives, or caregivers. |
| Shipping Container ADUs | Converted shipping containers (160–320 sq. ft.) used as compact rental units or studios. Eco-friendly and ideal for backyard use. |
| Second-Story ADU Additions | Build an ADU above your garage or home. Adds up to 1,200 sq. ft. while preserving your yard space. |
| Basement ADU Conversions | Convert your basement into a legal apartment (400–800 sq. ft.). Ideal for rentals or creating private living quarters. |
| Above-Garage ADU | Adds 400–1,000 sq. ft. above your existing garage. Offers private, elevated living space with a separate entry. |
| Corner Lot ADU | Leverage corner-lot access to build an ADU with private street entry and easier parking for tenants or guests. |
| Multi-Unit Property ADU | Add 1–2 ADUs to a duplex or triplex. Maximizes rental income while staying compliant with California law. |
| Tiny Home ADU | A 150–400 sq. ft. compact unit. Offers affordable housing, flexible placement, and lower utility usage |
| Loft-Syle ADU | Open-plan ADU with lofted ceilings and full light exposure. Best for creative studios or contemporary rental spaces. |
| Modular and Prefab Units | Factory-built ADUs delivered in 8–12 weeks. Offers fast installation with modern finishes and reduced construction disruptions. |
Our Proven ADU Design and Build Process
Our ADU process in Los Angeles includes six phases—from consultation to final delivery—designed for speed, code compliance, and a stress-free experience.
1
Free Consultation and Site Evaluation
We assess your lot and goals to recommend the best ADU type, helping you start with expert planning and local compliance clarity.
2
Custom Design and 3D Visualization
We develop custom ADU plans with 3D visuals so you can confirm every detail before construction begins.
3
Permit Filing and Code Compliance
We submit your ADU permits and ensure full compliance with Los Angeles code, preventing rejections and saving you weeks of delay.
4
Full-Scale Construction
We construct your ADU using durable materials and expert labor. The result is a safe, long-lasting living unit.
5
Final Walkthrough and Turnkey Delivery
We inspect the completed ADU with you, resolve issues, and deliver a fully finished, move-in-ready unit.
6
Post-Project Support
We provide continued support after delivery to address questions, upgrades, or maintenance, ensuring long-term ADU satisfaction.
How Much Does It Cost to Build an ADU in Los Angeles
Building an ADU in Los Angeles costs between $100,000 and $350,00, depending on ADU type, size, and site conditions. Garage conversions are the most affordable, while custom detached ADUs are the most expensive. New detached ADUs measure 500 to 800 square feet and can comfortably accommodate a one-bedroom or two-bedroom layout. 1,200 square feet is the maximum allowed size in Los Angeles. Larger, custom-built detached ADUs cost over $350,000.
Garage conversions are the most affordable ADU option. Converting a standard, 350 to 400 square feet two-car garage costs $100,000 to $160,000. This covers upgrades on insulation, plumbing, and electrical systems to meet residential standards.
Prefabricated or modular ADUs offer a middle ground in terms of pricing and construction time. These units typically cost $120,000 to $250,000, depending on size, finishes, and the amount of site preparation needed. Prefab ADUs are easier to install compared to traditional builds. However, the total cost could increase if the foundation and utility lines need rework.
Cost Range Table
This table outlines the typical cost ranges for common ADU types in Los Angeles, including their average size and construction benefits.
| ADU Type | Cost Range (USD) | Size (sq. ft.) | Key Notes |
|---|---|---|---|
| Garage Conversion | $100,000 – $160,000 | 350 – 450 | Most affordable; includes insulation, plumbing, and electrical upgrades |
| Detached ADU | $180,000 – $350,000+ | 500 – 1,200 | Offers full independence; great for rentals or multigenerational use |
| Modular / Prefab ADU | $120,000 – $250,000 | 400 – 800 | Faster install; may require added utility/foundation work |
Custom designs, luxury finishes, and complex site conditions may increase the cost beyond standard ranges. All estimates are developed based on site evaluation and design consultation.
Cost Factor List
These key factors influence ADU construction cost in Los Angeles:
- Property Layout & Site Conditions: Sloped or narrow lots raise costs due to excavation or access limits.
- · Utility Connections: Longer distances from the main house add trenching and hookup expenses.
- · Design Choices: Custom layouts and premium materials raise the final budget.
- · Permits & City Fees: Expect $5,000–$15,000 for LADBS fees, impact fees, and plan checks
Every quote is custom-built after site evaluation and design review. We provide clear, itemized pricing with no hidden fees.
See What Our Clients Are Saying
"Working with your team on our garage conversion was a fantastic experience. The process was smooth, the workmanship exceeded our expectations, and we love having a beautiful new space for our family."
"As a property investor, I’ve worked with several contractors, but none matched the professionalism and transparency of Los Angeles Advanced ADU Builders. My new detached ADU was completed on time and within budget. It is now ready to generate rental income.”
Tell Us About Your Space - We’ll Handle the Rest
Trust Los Angeles Advanced ADU to expertly manage your entire ADU project by combining local expertise and seamless project management.
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Learn About Building an ADU
Garage Conversion vs. Detached ADU: Which One Is Right for You?
Choosing between a garage conversion and a detached ADU depends on your space, budget, and long-term goals. This blog compares both options in terms of cost, privacy, design flexibility, and permitting. Whether you're maximizing rental income or housing family, you'll get clarity on the best fit for your property.
What You Need to Know About California’s New ADU Laws in 2025
California’s 2025 updates to ADU regulations make it easier than ever to build on your property—but there are key changes every homeowner must know. This blog breaks down the latest rules on setbacks, parking, lot splits, and streamlined approvals. Stay ahead of the curve and make informed decisions before starting your ADU project.
5 Design Ideas to Make Your ADU Feel Bigger and More Functional
Small space, big potential. Smart designs transform any ADU into a spacious, livable unit. In this blog, we share five proven layout and design strategies that enhance functionality without adding square footage. From open concepts to vertical storage, learn how to make every inch count.
ADU Construction FAQs
What is an ADU, and how does it work in Los Angeles?
An accessory dwelling unit (ADU) is a legal secondary home on your Los Angeles property, such as a detached unit or garage conversion. It can be used for family housing, long-term rentals, or guest stays.
What’s the difference between a detached ADU and an attached ADU?
A detached ADU is a separate structure from your main house, while an attached ADU shares a wall or is built as an addition to your existing home.
Do I need a permit to build an ADU in LA?
Yes, all ADU projects in Los Angeles require city permits and inspections for legal construction and occupancy.
Do you help with ADU permits and approvals?
Yes, we manage your ADU permits and approvals from start to finish, ensuring faster review and fewer revisions.
How do you handle zoning and code compliance?
We review your property’s zoning to ensure ADU design meets city codes and regulations before it's submitted to LADBS.
What types of ADUs can I build on my property?
You can build detached, attached, garage conversion, and junior ADUs—our team helps determine what fits your zoning and lot size.
Can I convert my garage into an ADU in Los Angeles?
Yes, you can convert your garage into an ADU in Los Angeles. We specialize in transforming garages into fully compliant living spaces.
Are prefab or modular ADUs allowed in Los Angeles?
Yes, Los Angeles allows both prefab and modular ADUs if they meet all local building codes and permit requirements.
Do you build shipping containers or modular ADUs?
Yes, we build both modular and shipping container ADUs after confirming feasibility with your property’s zoning and building codes.
What are the size limits and setback rules for ADUs in LA?
Detached ADUs can be up to 1,200 square feet, with specific setback and height requirements that vary by zoning. We’ll review your site for compliance.
Are there any ADU grants or financing options available in Los Angeles?
Yes, programs like CalHFA offer ADU grants and loans. We’ll help you explore local financing options available in Los Angeles.
Can I rent out my ADU legally in Los Angeles?
Yes, ADUs can be legally rented in Los Angeles for long-term stays, but short-term rentals (under 30 days) are restricted.
Is a site evaluation required before pricing my ADU?
Yes, we need to conduct a thorough site evaluation to get an accurate cost estimate for your project.
How long does it take to design and build an ADU?
The full process typically takes 6 to 12 months, depending on project size, design, and city approvals.
