#1 ADU Contractor in Highland
Custom Builds by Horizon Remodeling
Horizon Construction & Remodeling Inc. builds accessory dwelling units in Highland, handling design coordination, budgeting, permitting through the City of Highland Building and Safety Division, and material selection across every phase of the project. We work on detached backyard units, attached additions, and garage conversions throughout the city, including the tract neighborhoods of East Highlands Ranch and the older bungalow areas near the Palm Avenue historic core, where properties within the Highland Historic District may require a preservation review before exterior work begins.
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 Highland starts with understanding the rules that govern what you can build and where. California consolidated its ADU statutes into Government Code sections 66310 through 66342 in 2024, and those rules were updated again on January 1, 2026. Under the current law, square footage is calculated as interior livable space rather than overall footprint. Once you submit your application, the reviewing agency has 15 business days to confirm it is complete and 60 days to issue an approval or denial. Approval is ministerial, meaning no public hearing and no discretionary design review stands between your application and a decision.
In Highland, that application goes to the City of Highland Building and Safety Division. One detail that affects properties near the Palm Avenue historic core is worth raising before any plans are drawn. Part of the original 1891 townsite along Palm Avenue falls within the Highland Historic District, which was listed on the National Register of Historic Places in 2001. Any exterior work on a property within that boundary warrants a preservation review first, so we address that question at the very start of the process rather than midway through permitting.
San Bernardino County adopted a new ADU chapter, Development Code Chapter 84.36, at the Board of Supervisors on January 13, 2026. County standards allow a detached ADU from 200 up to 1,200 square feet and a junior ADU up to 500 square feet. Height limits are 25 feet attached and 18 feet detached, with two additional feet permitted to match an existing roof pitch. Side and rear setbacks are four feet, and detached structures must sit at least five feet apart. Two ADUs per lot are permitted, and properties of five acres or more may accommodate three units.
Sewer availability shapes feasibility on many parcels in this area. A sewer connection is required when a public line runs within 200 feet of the property line, and that threshold increases by 100 feet for each additional dwelling unit. When a connection is not required, the project proceeds on septic or an approved advanced treatment system. We bring Environmental Health into the conversation before a single plan is drafted so that sewer or septic constraints are known facts, not late surprises.
The character of Highland’s housing stock adds another layer of planning that matters on nearly every project. The city grew from that 1891 citrus townsite outward through decades of tract development leading up to incorporation in November 1987. The result is a mix of early bungalows near the old townsite and later single-story and two-story tract houses where a wall typically separates the kitchen from the family room. That layout affects where a detached unit can realistically be placed and how far electrical, water, and sewer lines will need to run, and we work through those specifics during our initial site review.
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 Highland ?
Horizon Construction and Remodeling is a licensed Class B general building contractor, bonded, and in business since 2009. We handle ADU projects in Highland from a single point of contact: one company draws the plan, coordinates with the City of Highland Building and Safety Division, and builds the unit. Before any design work starts, we work through the site questions that determine what is actually buildable on your parcel, including sewer or septic, access, and fire hazard zone classification.
Highland’s housing stock ranges from early citrus-era bungalows near the Palm Avenue historic core to single-story and two-story tract homes built around the time of the city’s November 1987 incorporation. Properties along Palm Avenue that fall within the Highland Historic District, listed on the National Register of Historic Places in 2001, may require a preservation review before exterior work proceeds, and we factor that into the planning process early. Specialty trade portions of every ADU are performed by appropriately licensed subcontractors we coordinate directly.
California state law provides consistent protections regardless of where your parcel sits: no owner-occupancy requirement, no sprinkler retrofit of the main house triggered by the new unit, and no impact fees on an ADU with 750 square feet or less of interior livable space. We also serve nearby communities including Loma Linda, Montclair, and Needles.
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ADU Contractor Services in Highland
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ADU Contractor in Highland FAQ
What is an ADU and why should I build one?
An accessory dwelling unit is a secondary home on your existing lot, built as a backyard cottage, a converted garage, or an in-law suite. Working with Horizon Construction and Remodeling on an ADU in Highland gives you a path to rental income, added family housing, or simply more usable space on a property that, in areas like the Palm Avenue historic core, may first warrant a preservation check before exterior work begins.
How much does it cost to build an ADU in California?
What an ADU Actually Costs in Highland
Cost depends on details no contractor can honestly quote from a website alone. The size of the unit, whether you are converting an existing structure or building new detached construction, what site work and utility runs your specific lot requires, and the finish level you select all move the number in different directions. What we can tell you is how state law shapes the financial picture. An ADU of 750 square feet or less of interior livable space is exempt from impact fees. School fees apply only when the unit exceeds 500 square feet. Connection fees for a conversion or junior ADU are limited because state law does not treat those as a new residential use, and adding an ADU cannot trigger a fire sprinkler retrofit requirement on your existing home. Highland’s tract houses from the decades surrounding the 1987 incorporation and the older bungalows near the Palm Avenue core each present different site conditions, so the permit path through the City of Highland Building and Safety Division will vary by property.
Any contractor quoting a firm price before walking your parcel is guessing. We inspect the property, confirm setbacks and utility conditions, and then provide a fixed scope and price you can hold us to. One warning worth stating plainly: the CalHFA ADU grant program is closed, its funding fully allocated, and the agency itself cautions that anyone offering to help you obtain an ADU grant is running a scam.
Do I need permits for an ADU in Highland?
Every ADU in Highland requires a building permit, and the application goes to the City of Highland Building and Safety Division. State law sets the review clock at 15 business days for a completeness determination and 60 days for an approval or denial decision. If your property uses a septic system or a well, Environmental Health gets pulled into the review, and the city will also check whether a sewer line runs within 200 feet of your property line, because connection is required when it does. For homes near the Palm Avenue historic core, exterior work may also warrant a preservation check before submittal. We handle the application, respond to any correction notices, and coordinate inspections from start to finish.
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 Highland?
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. handles ADU contracting in Highland from design through the final inspection with the City of Highland Building and Safety Division, coordinating every trade and keeping the project on budget and on schedule. Properties near the Palm Avenue historic core may require a preservation review before exterior work begins.
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 and Remodeling to schedule a free consultation, where we assess your property, talk through your goals, and deliver a detailed estimate that covers every phase of your Highland ADU project.
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Horizon is a licensed Class B general building contractor serving Highland and the surrounding Orange County communities.
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