#1 ADU Contractor in Los Angeles County
Custom Builds by Horizon Remodeling
Need more space or searching for an ADU contractor near Los Angeles County? Horizon specializes in seamless home additions and custom ADU construction in Los Angeles County, from extra bedrooms to backyard cottages and detached units. As your trusted ADU contractor near Los Angeles County, we manage design, budgeting, permits, and material selection—ensuring every project meets city codes and your vision. Our promise: safety, satisfaction, and a smooth build from start to finish. Let’s turn your ADU and home expansion dreams into reality.
SERVICES WE OFFER
Room Additions
Sunroom Additions
Garages & Conversions
Extensions
about the process
When it comes to enhancing your living space, room additions combined with Accessory Dwelling Unit (ADU) construction offer unparalleled versatility and value. These projects not only increase square footage but also provide additional living accommodations — whether for extended family, rental income, or work-from-home setups — making them a popular choice for homeowners seeking to maximize their property’s potential. According to California’s Department of Housing and Community Development, ADUs are a key solution to expanding housing options in urban and suburban neighborhoods.
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Navigating the Room Addition and ADU Construction Process
At Horizon Construction & Remodeling, we understand the complexities involved in room additions and ADU construction. From the initial planning stages to the final touches, our team works diligently to ensure a seamless integration with your existing home while adhering to local building codes and regulations.
Strategic Planning for Success
Our approach to room additions and ADU construction is rooted in strategic planning and value engineering. By consolidating design, engineering, and construction services under one roof, we streamline the process and provide you with a single point of contact for accountability. Our goal is to maximize efficiency and minimize costs without compromising on quality or craftsmanship.
Efficient Design-Build Coordination
As a design-build firm, we oversee every aspect of your project, from concept to completion. Our dedicated project managers work closely with our team of skilled craftsmen to ensure that your room addition and ADU construction proceed smoothly and according to schedule. With our comprehensive understanding of local building regulations, we navigate permit procedures seamlessly, keeping your project on track every step of the way.
Maximizing Value, Minimizing Stress
We are committed to delivering maximum value for your investment while minimizing stress throughout the remodeling process. Our transparent communication and customer-focused approach ensure that your needs and expectations are met at every stage of the project. From optimizing existing structures to leveraging cost-effective materials, we strive to make your room addition and ADU construction experience as seamless and stress-free as possible.
Trusted Excellence in Remodeling
Horizon Construction & Remodeling is proud to be recognized among the top remodeling contractors in Los Angeles and Orange County areas. With a proven track record of excellence and a portfolio of successful projects, we are dedicated to exceeding your expectations. Let us help you unlock the full potential of your home with our expert room addition and ADU construction services—contact us today to schedule a consultation and take the first step toward transforming your living space.
Other Remodeling Services We Offer
A modern kitchen adds functionality, comfort, and lasting value to your home. At Horizon Construction & Remodeling, our kitchen remodeling experts bring fresh ideas and professional project management tailored to your unique needs. From layout design to material selection, we prioritize delivering a high-standard kitchen that’s both beautiful and energy-efficient — enhancing the way you cook, gather, and live every day.
Whether you envision a classic Southern California pool or a fully customized backyard oasis, Horizon Construction & Remodeling delivers the highest level of quality and service. Our comprehensive pool design and remodeling services cover everything from layout and decking to built-in BBQs and final touches like landscaping. Let Horizon be your trusted partner in transforming your backyard into the perfect outdoor retreat.
If you are planning a complete bathroom remodel or simply want to change your tub, shower, update your plumbing fixtures, or make the space more efficient, our team at Horizon will help you through the process with expert advice, professional craftsmanship, and affordable options with beautiful results. Learn more about our bathroom remodeling services.
Transform your space with our expert interior work services. We offer a comprehensive range of solutions — from space planning and custom design to the selection of high-quality finishes and materials. Our team of experienced professionals works closely with you to create a space that’s both functional and stylish, tailored to your unique needs, goals, and budget. Whether you’re updating a single room or overhauling your entire interior, we bring precision, creativity, and craftsmanship to every project.
At Horizon, we believe your home is more than just four walls — it’s where life happens. It’s the place you relax, gather with family and friends, and create lasting memories. That’s why we offer a full range of exterior work services designed to elevate your outdoor living space. From patios and hardscaping to custom decks and exterior renovations, we help turn your vision into a dream yard that complements your lifestyle and enhances curb appeal.
At Horizon Construction & Remodeling, our expert team includes a dedicated design and planning division that works hand-in-hand with licensed architects and structural engineers. We take care of everything — from detailed plans and blueprints to securing city permits — so you don’t have to deal with delays or red tape. Our goal is to streamline the process and provide a fully approved set of documents that aligns with both your vision and city regulations, saving you time and stress.
Why Choose Horizon Remodeling As Your ADU Contractor In Los Angeles County ?
At Horizon Remodeling, your trusted ADU contractor near me, we specialize in high-quality home renovation and ADU construction solutions that enhance your living space and increase property value. With over 15 years of experience, we proudly serve Fullerton and surrounding areas, delivering expert craftsmanship in every project—from complete home remodels to custom room additions and accessory dwelling units (ADUs).
Need more living space? Our room addition and ADU contractor near me services are designed to meet your specific needs while complying with California’s latest building codes. Whether you’re adding a new in-law suite, rental unit, or structured expansion, Horizon ensures every detail is professionally handled for lasting results.
As a full-service home remodeling company, we also offer interior renovations like kitchen remodeling, bathroom upgrades, painting, flooring, and garage conversions. Every project is customized to your vision while maximizing beauty, functionality, and durability.
When you choose Horizon Remodeling as your go-to ADU contractor near me, you’re partnering with a dedicated team focused on integrity, transparency, and exceptional results. Contact us today for a consultation and let’s turn your renovation or ADU project into reality.
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Clients Love
EXCELLENT Based on 98 reviews Posted on conchita leslieTrustindex verifies that the original source of the review is Google. We recently had our roof remodeled by Horizon Construction and Remodeling, and we couldn't be more pleased with the outcome. David, our project manager, was exceptional—he kept us updated throughout the process and ensured everything went smoothly. The entire experience was amazing, and we truly enjoyed working with the team. We're already planning painting and insulation work in the near future and will definitely be reaching out to David and Horizon Construction and Remodeling againPosted on Sirous RouhiTrustindex verifies that the original source of the review is Google. Mason was very polite , professional and knowledgeable. This was our 2nd with horizon homes renovation. Mason did an excellent job. The work was done in timely and professional manner. Thanks Mason I will definitely recommend you to friends and family.Posted on Wesley BrownTrustindex verifies that the original source of the review is Google. Horizon has done 4 projects for us and each was completed very well, on schedule, and within budget.Posted on W Peter VosTrustindex verifies that the original source of the review is Google. There are so many positive things to list and describe, it is far better to wrap them all up into a single simple statement. Horizon Construction and Remodeling is a joy to work with, from planning to finish, from personnel to cost. Across the board, Horizon is excellent and we feel lucky to have found them.Posted on Jie HuTrustindex verifies that the original source of the review is Google. Great work! All individual workers (demo, shower prep, tile, electrician, plumber, wall, and shower door) worked with details, very responsible, and on time. The project management communicated with us well and did a wonderful job in organizing the work and inspections. The guest bathroom remodel took less than four weeks.Posted on Jeanne McEntireTrustindex verifies that the original source of the review is Google. After two years in my home in Dana Point, I was finally ready to remodel my kitchen. I knew what worked and didn’t work for me and my family. I chose Horizon to do my project, and am so pleased with the results! David was always available, was very detail oriented, and made amazing suggestions along the way. His crew were hard working and took good care of my home. My single story home is now fully open concept with new floors, fireplace, paint and of course the star of the home- the kitchen with the huge porcelain topped island, and top of the line finishings. Thank you, Horizon! I whole heartedly recommend you for anyone looking to remodel their home!Posted on Marlene BakerTrustindex verifies that the original source of the review is Google. Mark was here this morning to check out our Bathroom and we are sad we missed him! We wanted to give him a great big thank you and a hug! Please tell him thanks from us! Thanks to you too Enna, Caroline, Anna, Sam and your whole crew! You all have made this experience very pleasant! All of you have been kind, considerate and made us feel like we mattered! We appreciate you! We absolutely love our bathroom! It's beautiful and works so much better for us! I have been posting pictures and telling friends and family about the whole experience! I have one lady who may redo her bathrooms and another today that asked for your name to give to her daughter! We will continue to brag about you and our bathroom Thank you again! Marlene and DennisPosted on Eva ATrustindex verifies that the original source of the review is Google. There is some hiccups but overall I am satisfied with the quality of work. Just make sure that you include absolutely everything in the contract.
ADU Contractor Services In Los Angeles County
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ADU Contractor in Los Angeles County FAQ
What is an ADU and why should I build one?
An ADU, or Accessory Dwelling Unit, is a secondary housing unit built on your property—like a backyard cottage, garage conversion, or in-law suite. Building an ADU with Horizon Remodeling allows you to expand your living space, create a rental income opportunity, or provide independent living space for family members.
How much does it cost to build an ADU in California?
The timeline for a kitchen remodeling project varies depending on the size and complexity of your kitchen remodel. Most kitchen remodeling projects take approximately 4–8 weeks, covering design consultations, kitchen remodeling permits, demolition, kitchen plumbing and electrical work, and final kitchen installation.
Do I need permits for an ADU in Los Angeles County?
Yes, all ADU projects require proper permits to comply with California building codes. At Horizon Remodeling, we handle the entire ADU permit process for you, ensuring your project meets local regulations before construction begins.
How long does ADU construction take with Horizon Remodeling?
Most ADU construction projects take between 4 to 8 months from design to completion, depending on scope and permit approvals. Horizon Remodeling prioritizes efficient timelines while maintaining quality workmanship.
What types of ADUs can Horizon Remodeling build?
We specialize in building detached ADUs, attached ADUs, garage conversions, backyard cottages, and junior ADUs (JADUs). Our team can help you choose the right ADU style for your property and goals.
Can I build a detached ADU on my property in Los Angeles County?
Yes, if your property meets California zoning and space requirements. Horizon Remodeling will assess your site, secure the necessary permits, and build a fully detached ADU tailored to your preferences.
Is Horizon Remodeling licensed to build ADUs in my area?
Yes, Horizon Remodeling is fully licensed, bonded, and insured to build ADUs throughout Orange County and surrounding areas. We have over 15 years of experience delivering high-quality ADU projects.
What are the benefits of hiring Horizon Remodeling for my ADU project?
By choosing Horizon Remodeling, you gain a partner with expertise in ADU design, permitting, and construction. We manage the entire process from start to finish, ensuring your ADU meets building codes, stays within budget, and is completed on schedule.
Does Horizon Remodeling handle ADU design and permitting?
Absolutely! Horizon Remodeling provides complete ADU design services, including architectural plans and 3D renderings. We also handle city permits and inspections, streamlining your project and reducing stress.
How do I get started on an ADU with Horizon Remodeling?
Contact Horizon Remodeling to schedule a free consultation. We’ll assess your property, discuss your goals, provide design recommendations, and deliver a detailed estimate. From there, our team guides you step-by-step through every phase of your ADU project.








