ADU Builders in Orange County | Accessory Dwelling Units
Attached, detached, or garage conversions — built to California code.
Add Living Space to Your Property
California's ADU-friendly legislation has made accessory dwelling units one of the smartest investments an Orange County homeowner can make. Whether you need a rental unit, in-law suite, home office, or guest house, CCSI designs and builds ADUs that blend seamlessly with your existing property.
Orange County cities each have their own ADU overlay requirements on top of state law. Setback rules, height limits, parking exemptions, and utility connection fees vary from Irvine to Santa Ana to Newport Beach. CCSI has built ADUs across the county and knows what each jurisdiction requires — so your project doesn't stall in plan check.
From site assessment and architectural plans to foundation work and final finishes, our team handles the entire ADU build. We design units that feel like real homes — with full kitchens, bathrooms, proper HVAC, and thoughtful layouts that maximize every square foot.
ADU Types We Build
- Detached ADUs — standalone structures in your backyard
- Attached ADUs — additions to your existing home
- Garage conversions — transform your garage into living space
- Junior ADUs (JADUs) — up to 500 sq ft within existing footprint
- Two-story ADUs where zoning permits