Licensed ADU construction company in Orange County
ORANGE COUNTY CUSTOM ADU BUILDER
Building affordable and custom ADUs, with a focus on quality, energy efficiency, and design to fit your needs
This is Where
Your Dream 
Home 
Becomes Reality.
What's an ADU
An ADU is a secondary and architecturally diminutive unit on a property that already has a primary residential unit. A thoughtfully designed accessory dwelling unit provides extra living space, rental income, or a private retreat. As expert ADU builders in Los Angeles, we craft functional, high-value solutions tailored to your needs.
Custom ADU Homes
Garage Conversion ADU
ADU Design-Build
Steps to Build an ADU
Medium and Large construction projects in Orange County
Construction made simple. From ADUs to large-scale remodels, we guide you from start to finish.
L Square Construction specializes in permitted ADUs, but we also excel at whole-home renovations, multi-unit projects, and major upgrades across Orange County. Complex project? We handle it with expertise, reliability, and full compliance.
Let’s build your vision.
01
Custom ADU Design
We create a custom ADU design that fits your needs and budget, ensuring a smooth process as a trusted Los Angeles ADU contractor.
02
Design a Custom ADU Plan
Our team designs functional and stylish ADUs, from garage conversions to custom additions, ensuring quality and innovation in Los Angeles.
03
Permits for your Custom ADU
04
Construction – Building Your Custom ADU
Our expert ADU contractors in Orange County, CA, build your ADU with precision, staying on schedule and within budget.
05
Move In - Your Custom ADU is ready
Your new accessory dwelling unit is fully move-in ready, adding comfort, value, and extra living space to your property.
Want the Details?
Learn more about our seamless design and construction process.
Our Services
Custom ADU Homes
ADUs are the future of home living, offering rental income, extra space, or a private office. L Square Construction designs and builds custom ADUs to maximize your property’s value and functionality.
ADU Design-Build
Expand your living space, boost property value, and earn extra income with an ADU from L Square Construction. We handle everything from design to construction, ensuring a seamless, high-quality build.
Garage Conversion ADU
L Square Construction specializes in high-quality garage conversion ADUs that add living space, rental potential, or a private office. Our experienced builders deliver a seamless process and boost your property’s value and function.
Backyard Cottage Construction
Looking for a cozy cabin or cottage in Los Angeles? LS Construction crafts beautiful, high-quality cottages tailored to your unique needs with expert craftsmanship.
Granny Flat
At LS Construction, we build high-quality ADU granny flats for extra living space, rental income, or family housing. From design to permits, we handle it all — affordable, functional, and tailored to your needs.
In-law Suite
Looking for a house with an in-law suite in Los Angeles? LS Construction designs stylish, private spaces to keep loved ones close.
Benefits of having an ADU
Extra Income
A thoughtfully designed accessory dwelling unit (ADU) provides rental income, which is something very useful in such an expensive place as California.
Extra Space
An ADU provides extra living space, for relatives moving to your property or for new family moments
More Property Value
An ADU provides extra living space, for relatives moving to your property or for new family moments
Custom ADU Homes
Garage Conversion ADU
ADU Design-Build
Legal Requirements for ADUs in California
Building an ADU in Orange County requires adherence to local zoning laws and building codes. The regulations often include restrictions on the size of the unit, setbacks from property lines, and parking requirements. Depending on the location, some areas may have relaxed zoning laws, making it easier to build an ADU. It’s essential to consult with the Orange County planning department to ensure compliance with all requirements before starting construction.
Types of ADU
Expert ADU design and construction services customized to fit your space and lifestyle.
Garage Conversion
Home Conversion
Garage Addition
New Detached ADU
Home Addition
Junior ADU (JADU)
Interior finishing for garage conversion ADU
At L Square Construction, we believe garage conversions are about more than just structure — the interior finishing is key to creating a warm, functional home. We handle everything from insulation and drywall to lighting, plumbing, and kitchen installations, ensuring your converted garage feels like a true home, not an afterthought.
Luxury ADU and Guest House Builders in Orange County
As luxury ADU and guest house builders in Orange County, we understand that your vision might go beyond just adding space — you want elegance, comfort, and style. That’s why we design high-end ADUs that blend modern architecture with premium finishes. Whether it’s a detached guest suite, a private home office, or a vacation rental unit, we integrate smart layouts with luxurious touches like vaulted ceilings, designer kitchens, large windows, and top-tier appliances.
What sets our luxury builds apart?
- We collaborate with interior designers and architects
- We use premium materials like quartz, oak, and stone
- We offer energy-efficient systems and smart home tech
- We build ADUs that feel like upscale, standalone homes
At L Square Construction, we don’t just build additional units — we create stunning, functional extensions of your lifestyle.
Meet our CEO
Hello, I am Kiko - CEO of L Square...
Kiko brings a unique perspective as a Chinese-American entrepreneur, which enriches the company’s cultural and professional diversity. This background allows her to understand and address the needs of a wide range of clients, offering customized solutions that reflect a deep understanding of different cultural and social perspectives.
L Square Construction
Construction Company ADUs Orange County
L Square Construction is a licensed ADU construction company specializing in ADUs, home additions, and garage conversions. We handle architecture, structural engineering, and interior design in-house, ensuring top quality. Our expert team, with graduates from USC, UCLA, and UCI, brings fresh ideas and attention to detail to every project. As a trusted ADU contractor in Los Angeles, we focus on delivering custom ADU designs and innovative building solutions that meet your needs. Our goal is to create beautiful accessory dwelling unit designs while prioritizing service over profit.
Dependability. Integrity. Expertise.
We serve LA & Orange County.
One bedroom
540 sq. ft.
One bedroom
540 sq. ft.
One bedroom
540 sq. ft.
Garage to ADU Conversion Specialists
Why should you choose us for garage conversion?
• More than 200 garage conversions completed throughout Orange County. • Expertise in local ADU regulations • Complete turnkey solution from design to final inspection • Quick turnaround without compromising quality.With L Square Construction, your garage may become a lucrative asset, whether used for rental income, a guest suite, or multigenerational dwelling.As seen in:
City of Orange
City of Torrance
Living in a Thoughtfully
Designed Space.
Living in a Thoughtfully
Designed Space.
This New Space Might Steal the Spotlight from Your Main Home.
Backyard Cottage Construction
Transform your backyard into an energy-efficient ADU in Los Angeles with smart designs and solar solutions. Our custom ADUs reduce grid dependence while adding functional space and value to your property. Eco-friendly, efficient, and built for the future.
Cutting-Edge Energy Solutions
Innovative designs that reduce your carbon footprint.
Designed for Efficiency
Over 2x more energy-efficient than traditional homes.
AS FEATURED ON
Types of ADU
Expert ADU design and construction services customized to fit your space and lifestyle.
If you are looking for a Construction Company
Ready to Build Your ADU? Stop dreaming—start building. Get your free, no-obligation quote today and let’s turn your Orange County property into a smarter investment
Costs Associated With Building an ADU
From design to permits to construction, we handle everything.
The costs of building an ADU in Orange County can vary significantly based on factors such as the size of the unit, design complexity, and the type of ADU you choose. On average, the total cost of building an ADU ranges from $120,000 to $250,000. This includes site preparation, foundations, framing, plumbing, electrical systems, and interior finishes. Smaller or prefab units can be more affordable, while custom-built, larger units will be on the higher end of the spectrum. Additional costs such as permits, inspections, and utility connections should also be factored into the budget.
Local regulations for building an ADU
Beware!
Building an ADU in Orange County requires adherence to local zoning laws and building codes. The regulations often include restrictions on the size of the unit, setbacks from property lines, and parking requirements. Depending on the location, some areas may have relaxed zoning laws, making it easier to build an ADU. It’s essential to consult with the Orange County planning department to ensure compliance with all requirements before starting construction.
Typical Construction timeline for an ADU
Built by experts, designed for longevity.
The construction timeline for an ADU in Orange County can range from 6 to 12 months, depending on the type of unit, complexity of the project, and the time required to obtain permits. Smaller projects such as garage conversions may be completed more quickly, while custom detached units can take longer due to the need for more extensive design work, permits, and construction efforts. Be sure to plan for potential delays due to zoning approvals or weather conditions.
Why should I consider an ADU?
If you are planning to convert your garage into a room, or need home remodeling services in California
1. Extra Income
Rent it out for passive income.
Short-term rentals (Airbnb, VRBO) can be highly profitable.
2. Increased Property Value
ADUs boost home value by adding livable space.
Attracts buyers looking for multi-generational or rental potential.
3. Affordable Housing Solution
Cheaper than buying a new home.
Helps family members (aging parents, college students) live nearby.
4. Flexible Living Space
Use it as a:
✅ Home office
✅ Guest house
✅ Art studio or gym
5. Faster Approval Than New Construction
Many cities streamline permits for ADUs to ease housing shortages.
6. Sustainability Benefits
Smaller footprint = lower energy use.
Can be built with eco-friendly materials.
Key Steps to Get Started
Check local zoning laws (some areas have relaxed ADU rules).
Plan your budget (prefab ADUs can save time/money).
Hire a contractor experienced in ADUs.
Apply for permits before construction
Frequently Asked Questions
An accessory dwelling unit (ADU) is a small, independent living space on your property. It’s ideal for rental income, guest housing, or an in-law suite for family members.
Costs vary based on size and design. Our ADU cost calculator provides an estimate, and as a trusted ADU construction company, we offer accurate quotes and financing options.
Yes! A garage conversion ADU is a popular way to add extra living space. As experienced garage conversion builders, we ensure a seamless process from permits to completion.
Use our home addition cost estimator or construction price calculator for an estimate. Our ADU design-build team in Orange County provides customized solutions to fit your budget.
Absolutely! We specialize in ADU projects in Los Angeles and Orange County, creating efficient and stylish living spaces.
A professional ADU contractor in Los Angeles, like LScontractor, ensures compliance with city regulations, high-quality construction, and efficient project management. We handle everything from custom ADU designs in Orange County to final inspections.
Yes! We design and build cabins in Los Angeles and Orange County, as well as backyard cottages for homeowners seeking extra space or rental opportunities.
Yes! Smart home automation reduces energy waste by optimizing lighting, climate control, and appliance usage. Automated schedules and thermostat adjustments can help lower energy bills.
Our systems use encrypted connections, multi-factor authentication, and real-time alerts to protect your home and data. Features like smart locks, motion sensors, and remote monitoring provide additional security.
Yes! Our smart home solutions are designed to be scalable. You can start with basic automation and add features like security upgrades, smart entertainment, or climate control whenever you’re ready.
Anaheim, Los Angeles, Santa Ana, Irvine, Huntington Beach, Garden Grove, Orange, Fullerton, Costa Mesa, Newport Beach, Mission Viejo, Tustin, Yorba Linda, Lake Forest, Laguna Niguel, Fountain Valley, Westminster, Brea, Placentia, Cypress, Seal Beach, Aliso Viejo, Laguna Hills, La Habra, San Clemente, Dana Point, Los Alamitos, Villa Park, Rancho Santa Margarita
Need more space? Let’s build something you’ll love!
Your home should grow with you—let’s make it happen!
Big dreams for your home? We’re here to bring them to life.
From ideas to reality, we’re with you every step of the way.
Affordable ADU Builders
Premium Quality, Not Premium Prices
Get a cost-effective ADU without cutting corners. Our transparent pricing and efficient processes make accessory dwelling units accessible for Orange County homeowners, whether for rental income or multigenerational living.Construction Companies
Where Vision Meets Precision
As a leading Orange County construction company, we handle projects of all scales—from ADUs to custom homes—with the same commitment to craftsmanship, timelines, and your peace of mind.Converting a Room into a Garage
More Than Just Four Walls
Repurpose underused rooms into functional garages or flexible spaces. We optimize layouts, storage, and durability to match your lifestyle needs while adhering to local building codes.Remodeling and ADU Contractors
Two Services, One Trusted Team
Whether you’re remodeling your home or adding an ADU, we streamline both processes with cohesive design, permitting expertise, and minimal disruption to your daily life.Building ADUs in Orange County
Building an Accessory Dwelling Unit (ADU) in Orange County is a smart way to increase property value, generate rental income, or provide housing for family members, thanks to relaxed state laws and streamlined permitting processes. Homeowners can choose from detached backyard units, garage conversions, attached additions, or junior ADUs (JADUs), depending on their needs and property layout. The process involves checking local zoning rules, designing the unit, securing permits, and hiring licensed contractors for construction. With financing options like home equity loans, construction loans, and potential incentive programs, adding an ADU is an accessible and profitable investment in Orange County’s competitive housing market. Ready to get started? Consult with local ADU experts to explore your options today!
Anaheim, Los Angeles, Santa Ana, Irvine, Huntington Beach, Garden Grove, Orange, Fullerton, Costa Mesa, Newport Beach, Mission Viejo, Tustin, Yorba Linda, Lake Forest, Laguna Niguel, Fountain Valley, Westminster, Brea, Placentia, Cypress, Seal Beach, Aliso Viejo, Laguna Woods, La Habra, San Clemente, Dana Point, Quail Hill, Los Alamitos, Galivan, Villa Park, East Irvine, Rancho Santa Margarita, Laguna Hills