ADU Construction in Southern California

Modeno Builders Inc is a licensed ADU (Accessory Dwelling Unit) contractor serving Orange County, Los Angeles, Ventura, and Riverside County. We build detached ADUs, attached ADUs, garage conversion ADUs, and junior ADUs — helping homeowners maximize their property value and generate rental income.

Our ADU Services Include:

Add Value. Generate Income.

California's ADU laws make it easier than ever to build on your existing property. Modeno Builders handles everything from permits to final inspection. Serving all of Southern California with 2,000+ completed projects.

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ADU Construction in Southern California

An accessory dwelling unit is one of the highest-leverage moves a SoCal homeowner can make. It generates rental income, adds resale value, houses aging parents or adult children, and — unlike a pool — tends to pay for itself. Since California's 2017 reforms, building one is closer to a standard remodel than a rezoning fight.

Modeno Builders builds ADUs across Orange County, Los Angeles, Ventura, and Riverside — garage conversions, attached units, and ground-up detached builds — and manages the permits, engineering, and utility connections in-house.

Types of ADUs we build

Why ADUs pay back

Most well-built ADUs cover their build cost in 6–12 years of rental income, and appraisers credit 60–80% of build cost to your home's appraised value. The income stream and the optionality — house family now, rent later — are often worth more than the appraisal bump.

ADU Construction FAQs

Garage conversions $90K–160K, attached ADUs $200K–340K, detached ADUs $260K–420K, high-end detached $450K–700K+. Per square foot: $200–350 for conversions, $350–650 for new construction.
10–16 months end to end: design 6–12 weeks, permits 4–12 weeks, construction 4–7 months, utility hookups 2–6 weeks. California mandates 60-day permit approval on complete applications.
State law allows a detached ADU up to 1,200 sq ft, an attached ADU, and a JADU up to 500 sq ft on most single-family lots. Many lots can support two ADUs plus the main residence — no public hearing required.
In 2026, a 750 sq ft ADU rents for $2,800–3,800/month in coastal OC, $2,400–3,400 in LA, $1,800–2,400 in the Inland Empire. Most cover their build cost in 6–12 years.
No — California eliminated the owner-occupancy requirement for ADUs. You can rent the ADU even if you don't live in the main house.
Yes. CSLB License #1151614, fully bonded and insured. BBB Accredited Business.

Considering an ADU?

Schedule a Free In-Home Consultation or call (818) 970-0032