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“Have a Vision? We Build It Together.”
Have a question about our construction services, pricing, or ongoing projects? Our team is ready to assist you.
Maximize Your Property's Potential in the Hills
In a city known for its spacious lots and rolling landscapes, an Accessory Dwelling Unit (ADU) is the smartest way to add value to your Chino Hills home. Whether you’re looking to provide a private space for aging parents, a rental for passive income, or a high-end guest cottage, we specialize in ADUs that feel like a natural extension of your primary residence. See our main ADU construction page for a full breakdown of ADU types, statewide rules, and pricing.
- Zoning Experts: We navigate the Chino Hills Planning Division requirements, ensuring your set-backs and height restrictions are met the first time.
- Architectural Harmony: From the Mediterranean villas of Vellano to the traditional homes in Butterfield Ranch, we match your ADU’s exterior to your existing home’s aesthetic.
- Hillside Engineering: Specialized foundation expertise for properties with the unique topography found in Chino Hills, including sloped lots and retaining wall considerations common throughout the city’s hillside neighborhoods.
- SB 543 Fast-Track Permitting: We submit every Chino Hills ADU application under California’s 2026 fast-track rules, so the city has just 15 business days to review your paperwork for completeness before it’s automatically deemed complete by law.
- Right-Sized for Your Lot: Whether you’re on a compact lot in a newer tract or a sprawling hillside parcel, we help you choose between a JADU, garage conversion, attached, or detached ADU based on what your property can actually support.
Types of ADUs We Build in Chino Hills
- Garage Conversion ADU: The fastest, most affordable option, reusing your existing foundation and walls. Ideal for Chino Hills homeowners who don’t rely on garage parking and want quick rental income. See our garage conversion page for details.
- Attached ADU: Shares a wall with your main house, keeping utility hookups simpler and less expensive than a fully detached build.
- Detached ADU: A standalone structure in the backyard, well suited to Chino Hills’ larger lots in neighborhoods like Vellano and The Preserve, offering maximum privacy and rental value.
- Junior ADU (JADU): A smaller unit built within your existing home’s footprint, capped at 500 sq. ft., ideal for aging parents or adult children who want privacy while staying close.
Not sure which type fits your lot? Our guide, Garage Conversion vs. ADU: Which Is Better?, breaks down the trade-offs side by side.
Chino Hills ADU Cost Estimate
Chino Hills’ mix of hillside topography and larger tract-home lots means cost can vary more from property to property than in flatter, denser cities. Here’s what homeowners typically budget for:
ADU Type | Typical Cost Range | Typical Timeline | Best For |
|---|---|---|---|
Junior ADU (JADU) | $40,000 – $100,000 | 2–4 months | Family members, lowest-cost option |
Garage Conversion ADU | $50,000 – $150,000 | 3–5 months | Fastest path to rental income |
Attached ADU | $80,000 – $250,000 | 5–8 months | More space, simpler utility hookups |
Detached ADU | $130,000 – $400,000+ | 6–10 months | Max privacy and rental value on larger hillside lots |
What can move your number up or down in Chino Hills specifically:
Cost Factor | Impact |
|---|---|
Slope and hillside grading | Sloped lots common throughout Chino Hills may need additional foundation engineering or retaining wall work. |
Neighborhood architectural style | Matching Vellano’s Mediterranean villas or Butterfield Ranch’s traditional style adds to finish-level cost versus a basic build. |
Utility hookup distance | Detached ADUs farther from the main house cost more to connect to water, sewer, and electrical. |
SB 543 fee exemption | ADUs under 500 sq. ft. of interior livable space are exempt from school impact fees, potentially saving $10,000+. |
These are starting ranges. Every Chino Hills property is different, especially on hillside lots, so we provide a written, itemized estimate after the first site walkthrough. Book a free consultation and we’ll give you real numbers for your property.
Our Chino Hills ADU Process
- Property evaluation and feasibility consultation. We visit your property, check zoning, and confirm what you can legally build, including any hillside or slope-specific considerations.
- Architectural design and planning. We design layouts that match your lot, your neighborhood’s style, and your budget.
- Permit preparation and city approvals. We submit and track your permit through the Chino Hills Planning Division using the latest SB 543 fast-track rules.
- Full construction management. We manage every trade under one team, so you don’t juggle contractors. See our full range of construction and remodeling services.
- Final inspection and project completion. We handle city sign-off and walk you through your finished unit.
Recently Completed Projects
Why Chino Hills Homeowners Choose ACT Construction
ACT Construction has operated as FAM Promotions, Inc. DBA ACT Construction since 1993, holding California General Contractor License #883252, and has built ADUs throughout Chino Hills, from Vellano to Butterfield Ranch to The Preserve, for over 26 years.
- 33+ years building in Southern California. Founded in 1993.
- Licensed general contractor. California License #883252.
- One point of contact. From design to final inspection.
- Fast-track permit experience. We know the 2026 SB 543 process and the Chino Hills Planning Division extremely well.
- Transparent pricing. No hidden change orders.
If you’re also considering a full home remodel alongside your ADU, we also handle whole house remodeling and kitchen remodeling throughout Chino Hills.
Frequently Asked Questions
How much does an ADU cost to build in Chino Hills?
Most Chino Hills ADUs cost between $50,000 for a garage conversion and $400,000+ for a large detached unit, with hillside lots sometimes requiring extra foundation work that adds to the cost.
Do I need a permit to build an ADU in Chino Hills?
Yes. All ADUs require approval through the Chino Hills Planning Division, including zoning, setback, and height restriction review. We handle the entire plan-check process for you.
Can I build an ADU on a sloped or hillside lot?
Yes. We have specialized foundation expertise for the sloped topography common throughout Chino Hills, and we evaluate slope and retaining wall needs during your initial site visit.
How long does ADU construction take in Chino Hills?
Most projects take 4 to 10 months from design to move-in, depending on ADU type and any hillside-specific engineering required.
Will my ADU match my neighborhood's architectural style?
Yes. Whether your home is a Mediterranean villa in Vellano or a traditional-style home in Butterfield Ranch, we design your ADU’s exterior to match.
Can I rent out my Chino Hills ADU?
Yes. California law allows ADU rentals statewide. Short-term rentals under 30 days may be restricted locally, so we confirm current Chino Hills rules with you during planning.
Is a garage conversion cheaper than a full ADU in Chino Hills?
Usually, yes. A garage conversion reuses your existing foundation and walls, which cuts cost and build time. See our garage conversion vs. ADU comparison for a full breakdown.
Do you serve areas near Chino Hills too?
Yes. Alongside Chino Hills, we serve Yorba Linda, Diamond Bar, San Dimas, Irvine, Anaheim Hills, Walnut, Rancho Cucamonga, Claremont, and Upland.
