#1 ADU Contractor in Lemon Heights
Custom Builds by Horizon Remodeling
Horizon Construction & Remodeling Inc. builds accessory dwelling units and home additions for homeowners in Lemon Heights, handling design coordination, budgeting, material selection, and permits from start to finish. Because Lemon Heights is unincorporated county territory, permits run through OC Development Services rather than a city building department, and projects on these large custom lots also fall under the North Tustin Specific Plan, which layers additional height and land use requirements on top of standard county zoning. We manage all of that so you do not have to.
Services We Offer
How Our ADU Process Works
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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Finding the right adu contractor in Lemon Heights means understanding a permit process that works differently than most Orange County cities, because Lemon Heights is unincorporated county territory and applications go to OC Development Services rather than any city building department. On top of standard county zoning, most of the area falls inside the County of Orange North Tustin Specific Plan, which layers its own land use districts and height limits over the base code. That combination shapes what you can build and where before a single line gets drawn.
California ADU law, codified in Government Code sections 66310 through 66342 and updated again on January 1, 2026, gives homeowners meaningful protections regardless of which agency reviews the application. Square footage is now measured as interior livable space. OC Development Services has 15 business days to determine whether a submission is complete and 60 days to approve or deny it. Approval is ministerial, meaning no public hearing and no discretionary design review.
State law also sets firm limits on what any local agency can restrict. A unit cannot be capped below 850 square feet of interior livable space, or 1,000 square feet with more than one bedroom. Side and rear setbacks cannot exceed four feet. Owner-occupancy cannot be required, a new ADU cannot trigger a sprinkler retrofit of the main house, and there are no impact fees on a unit of 750 square feet or less.
The parcel itself drives most of the remaining decisions. Lemon Heights lots range from roughly a quarter acre to several acres, and the custom hillside houses built across the twentieth century sit on grade changes that affect utility runs, equipment access, and whether a detached build or a garage conversion is the more practical path. We walk the property and check all of that before drawing anything.
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 Lemon Heights ?
Horizon Construction and Remodeling is a Class B general building contractor, licensed and bonded, with over 15 years of design-build experience. A detached ADU is essentially a self-contained small house placed on a lot that already has a primary residence. It involves foundation work, framing, roofing, a full building envelope, a kitchen, a bathroom, and both plumbing and electrical service, all coordinated under one contractor rather than split across separate hires.
Lemon Heights sits in unincorporated county territory, so permits run through OC Development Services rather than a city building department. Much of the area also falls inside the North Tustin Specific Plan, which layers land use districts and height limits on top of standard county zoning. We account for those requirements during design, not after, because on a design-build project the drawing decisions and the construction constraints are the same decisions made at the same time.
The large hillside parcels common throughout Cowan Heights, Panorama Heights, Red Hill, and the broader North Tustin area often give genuine room for a detached ADU. Our Fullerton office puts Lemon Heights well within our regular working area. We also build ADUs in Tustin and Villa Park.
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ADU Contractor Services in Lemon Heights
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ADU Contractor in Lemon Heights FAQ
What is an ADU and why should I build one?
An ADU is a secondary housing unit on your property, such as a backyard cottage, garage conversion, or in-law suite, and building one with Horizon Construction and Remodeling can expand your living space, generate rental income, or give family members a place of their own. On the large hillside lots common across Lemon Heights and the wider North Tustin area, there is often room to make that work well.
How much does it cost to build an ADU in California?
Putting a real number on an ADU project in Lemon Heights requires more information than any website can capture. The cost shifts depending on whether you are converting an existing structure or building a new detached unit from scratch, how much site work your hillside lot demands, how far utility lines need to run, and what finish level you choose. Because Lemon Heights is unincorporated county territory governed by OC Development Services and subject to the North Tustin Specific Plan, the permitting path adds another layer of review on top of standard county zoning, and that can affect scope and scheduling in ways that only a property walkthrough will reveal. Anyone who quotes you a firm price before seeing the parcel is guessing, and that guess rarely holds.
What we can tell you is how state law limits certain costs. An ADU under 750 square feet of livable space is exempt from impact fees, school fees apply only above 500 square feet, and connection fees for a conversion or junior ADU are capped because the state does not classify those as a new residential use. Adding an ADU also cannot force a fire sprinkler retrofit on your existing home. One caution worth stating plainly: the CalHFA ADU grant program is closed and fully allocated, and the agency itself has said that anyone offering to help you obtain that grant is running a scam.
Do I need permits for an ADU in Lemon Heights?
An ADU in Lemon Heights always requires a building permit, though approval is ministerial rather than discretionary, meaning no hearing or design review board gets involved. Because Lemon Heights is unincorporated county territory inside North Tustin rather than part of the City of Tustin, applications go through OC Development Services, which also administers the North Tustin Specific Plan requirements that apply across much of the area. State law gives the agency 60 days to approve or deny a complete application, or 30 days when a pre-approved plan is used, with a 15-business-day completeness determination before that clock starts. We prepare and submit the full package and carry it through every inspection, so the process does not fall back on the homeowner.
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 Lemon Heights?
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 18 years of experience delivering high-quality ADU projects.
What are the benefits of hiring Horizon Remodeling for my ADU project?
Horizon Construction & Remodeling Inc. manages ADU projects in Lemon Heights from design through final inspection, coordinating permitting with OC Development Services and keeping the work aligned with the North Tustin Specific Plan requirements that govern this unincorporated area.
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?
Reach out to Horizon Construction & Remodeling Inc. to schedule a free consultation, where we assess your property, talk through your goals, and deliver a detailed estimate covering every phase of your ADU project in Lemon Heights, including the county permit process through OC Development Services.
Recent ADU and Garage Conversions
Three completed ADU and garage conversion projects from our Orange County portfolio. Every project below was built in San Clemente. Nothing loads from YouTube until you press play.
ADU project in San Clemente
ADU project in San Clemente
ADU project in San Clemente
Built by Horizon Construction & Remodeling, Inc. Licensed Class B general building contractor.
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Horizon is a licensed Class B general building contractor serving Lemon Heights and the surrounding Orange County communities.
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