#1 ADU Contractor in Fontana
Custom Builds by Horizon Remodeling
Horizon Construction & Remodeling Inc. builds accessory dwelling units and home additions throughout Fontana, managing design, budgeting, permits, and material selection from start to finish. Because portions of Fontana fall inside a special wind region with design wind speeds that can reach 135 mph depending on risk category, structural planning matters more here than in many surrounding cities, and we coordinate that work through appropriately licensed subcontractors. All permit applications go through the City of Fontana Building and Safety Division, and we handle that process on your behalf.
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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ADU Permits and Local Rules in Fontana
Finding the right adu contractor in Fontana 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 another update took effect January 1, 2026. Under the current law, square footage is calculated as interior livable space rather than overall footprint, an agency has 15 business days to confirm an application is complete, and 60 days to approve or deny it. Approval is ministerial, meaning no public hearing and no discretionary design review stands between a complete application and a decision.
In Fontana, that application goes directly to the City of Fontana Building and Safety Division. One detail that sets Fontana apart from many Southern California cities is its wind load requirement. The city’s own Building and Safety wind load bulletin identifies portions of Fontana as a special wind region, with design wind speeds ranging from 116 to 135 mph depending on risk category. Structural plans for any new detached unit must account for those loads, which affects framing specifications and engineering costs from the start.
San Bernardino County adopted Development Code Chapter 84.36 at the Board of Supervisors on January 13, 2026, making it the most current county ADU ordinance we work under. Published standards allow a primary ADU between 200 and 1,200 square feet, a junior ADU up to 500 square feet, attached height up to 25 feet, and detached height up to 18 feet with two additional feet permitted to match an existing roof pitch. Side and rear setbacks are four feet, with five feet of separation required between detached structures. Two ADUs per lot are permitted, and properties of five acres or more may add three units.
Sewer access drives feasibility on many Fontana parcels. A connection is required when a sewer line runs within 200 feet of the property line, with that distance increasing by 100 feet for each additional dwelling unit. Where sewer is not reachable, the project relies on septic or an advanced treatment system. We engage Environmental Health before a single plan is drawn so that question is answered early rather than mid-permit.
The age and layout of your home shapes everything else. The older stucco ranch homes in the south end of Fontana typically sit on lots where utility runs to a detached unit can be longer and where setback math gets tight. In the newer north end neighborhoods like Sierra Lakes and Hunter’s Ridge, the two-story plans with barrel tile roofs often have more usable rear yard, and the open kitchen-to-family-room layout can make a junior ADU conversion more straightforward. We assess both the lot and the existing structure together before recommending which ADU type fits your property.
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 Fontana ?
ADU Construction in Fontana by a Licensed General Contractor
Horizon Construction and Remodeling builds accessory dwelling units in Fontana as a licensed Class B general building contractor, bonded, and in business since 2009. One company handles the drawings, coordinates with the City of Fontana Building and Safety Division, and carries the project through to the final inspection. That single point of responsibility matters on a project type where design, permitting, and construction decisions are tightly connected.
Fontana’s housing stock shapes how ADU projects actually start. A stucco ranch in the older south end near Southridge Village sits on a different lot configuration than a two-story plan with a barrel tile roof in north Fontana near Sierra Lakes or Hunter’s Ridge. Before design begins, the feasibility questions come first: utility connections, access, fire hazard zone classification, and what the site can physically support. Fontana also falls within a special wind region, with design wind speeds between 116 and 135 mph depending on risk category, so structural design reflects those local load requirements from the start.
State law provides several baseline protections that apply to every Fontana parcel. There is no owner-occupancy requirement for an ADU, building one does not trigger a sprinkler retrofit on the main house, and units with 750 square feet or less of interior livable space are not subject to impact fees. We serve homeowners throughout Fontana, including Downtown Fontana, Southridge Village, Sierra Lakes, and Hunter’s Ridge. Contact us to request a free estimate.
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ADU Contractor Services in Fontana
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ADU Contractor in Fontana FAQ
What is an ADU and why should I build one?
An accessory dwelling unit is a self-contained secondary home on your existing lot, taking the form of a converted garage, a detached backyard structure, or an attached in-law suite. Building one with Horizon Construction and Remodeling can add rental income, house extended family, or simply give your Fontana property more usable living space.
How much does it cost to build an ADU in California?
What an ADU Actually Costs in Fontana
No contractor can give you an honest number from a web page alone. The real cost depends on whether you are converting an existing structure or building a new detached unit, how large the finished space will be, what site work your lot requires, and the finish level you choose. What the law does spell out is where your money is protected. A unit with 750 square feet or less of interior livable space is exempt from impact fees. School fees only apply above 500 square feet. Connection fees for a conversion or junior ADU are capped, because state law does not treat those as a new residential use. And adding an ADU cannot force a fire sprinkler retrofit on your existing home.
Because parts of Fontana fall inside a special wind region, with design wind speeds between 116 and 135 mph depending on risk category, structural details matter from the first drawing. That is one reason we walk every property before quoting anything. We confirm setbacks, utility runs, and wind-load requirements, then deliver a fixed scope and price you can hold us to. One more thing worth saying plainly: the CalHFA ADU grant program is closed and fully allocated, and the agency itself warns that anyone promising to help you obtain that grant is running a scam.
Do I need permits for an ADU in Fontana?
Every ADU in Fontana requires a building permit, and the application goes to the City of Fontana Building and Safety Division. State law sets the review timeline at 15 business days for a completeness determination and 60 days to issue an approval or denial, and city guidance already reflects those standards. If the property relies on a septic system or a well, Environmental Health gets pulled into the review. Sewer proximity also gets checked, since connection is required when a public sewer line falls within 200 feet of the property line. Fontana’s own wind load bulletin designates portions of the city as a special wind region with design speeds from 116 to 135 mph depending on risk category, so structural drawings need to account for that from the start. Horizon handles the submittal, tracks correction notices, and coordinates all required inspections.
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 Fontana?
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 design, permitting through the City of Fontana Building and Safety Division, and construction as a single coordinated process, keeping the project on budget and code-compliant from the first plan review to the final inspection.
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 Fontana property, talk through your goals, and deliver a detailed estimate covering every phase of your ADU project.
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Horizon is a licensed Class B general building contractor serving Fontana and the surrounding Orange County communities.
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