Prefab / Modular ADU near Mission Viejo, CA

ADUs are secondary units built on existing lots. ORR Construction builds detached ADUs, garage conversions, JADUs & in-law suites in California. Costs range $50–$300/sq ft. California laws like SB 897 simplify the permitting process.

ADU Design Homes is a full-service ADU design and build firm in Los Angeles and Orange County. They handle detached ADUs, JADUs, garage conversions, permitting, engineering, and construction under one roof.

Prefab vs. stick-built ADUs explained. Homeplex offers the Clever ADU, an HCD-certified modular unit built all-electric in a factory, saving 5–6 months vs. traditional construction. Costs vary based on site conditions.

ADU Custom Homes is a licensed California ADU contractor with 35+ years of experience serving LA, Orange & Riverside counties. They specialize in detached ADUs, garage conversions & additions, managing projects from permits to Certificate of Occupancy.

Full Circle Builders offers custom ADU construction in Riverside County & the Inland Empire. Detached ADUs start at $185,000 (590 sq ft, 1BD/1BA). Container homes also available. Turn-key builds, permitting assistance included.

Paramount Manufactured Sales in Riverside offers Skyline Homes-built ADUs for Southern California homeowners in LA, Orange, Riverside, San Bernardino & San Diego Counties. Models range from 479–849 sq ft. California law now allows detached ADUs up to 1,200 sq ft.

Eureka Modular builds steel frame modular ADUs and single family homes. Steel framing offers durability, design flexibility, and sustainability. Ideal for detached ADUs, backyard cottages, granny flats, and casitas with efficient, precise construction.

Cali ADU is a top Los Angeles ADU builder offering custom and pre-designed accessory dwelling units, garage conversions, and granny flats. Fixed pricing, fast permitting, and expert project management ensure stress-free builds from design to move-in.

Proteus Homes is a custom home and ADU builder with 30+ years of experience in the Southwest US. They offer full-service ADU construction, including design, permitting, and panelized off-site fabrication, with move-in-ready homes in under three months.

ADU Los Angeles (ADLA) is a specialized ADU contractor serving LA County. They offer consulting, custom design, construction, garage conversions, basement ADUs, attached and detached units, helping homeowners maximize property value.

Avica Construction & Development Inc is a licensed LA-based ADU contractor building detached ADUs, garage conversions, attached ADUs & JADUs across Los Angeles, Orange County & San Bernardino County, managing design, permits & construction.

Crest Backyard Homes is San Diego's trusted ADU builder, specializing in prefab, detached ADUs, granny flats & garage conversions. Their all-inclusive team guides homeowners from design to completion, ensuring code-compliant, high-quality accessory dwelling units.

ABODU offers factory-built, fire-resistant ADUs installed in a single day. HCD-approved and AB 462-compliant, their prefab units help wildfire rebuild families return home faster, with Certificates of Occupancy issued before primary dwelling completion.

North County ADU Construction is a local ADU contractor serving north San Diego County. They specialize in garage conversions, JADUs, detached ADUs, and prefab installs. With 500+ builds and a 96% satisfaction rate, they handle design, permitting, and construction.

US Modular Inc. is a trusted ADU builder in Riverside County, CA, with 35+ years of experience. They offer prefab ADUs, garage conversions & casitas starting at $150,000, completed in 6–9 months.