Prefab / Modular ADU near Montclair, CA

Ataman Studio is a trusted ADU contractor in Los Angeles, serving all of California. Full-service design, permitting, and construction for detached ADUs, garage conversions, and in-law units, with compliance to local zoning and state regulations.

Addition Builders LA is a full-service ADU contractor in Los Angeles offering custom ADUs, prefab units, and garage conversions. Licensed, bonded, and insured, they manage design to construction, completing projects in as little as nine months with transparent pricing.

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.

ADU Custom Home Source, based in Riverside, CA, specializes in custom manufactured homes and ADUs. Serving Southern California, they handle design, permitting, financing, and installation, offering granny flats, casitas, and detached ADUs.

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.

LADU is a full-service ADU builder in Los Angeles managing design, permits, and construction end-to-end. Serving LA, Orange, San Diego & more counties, they offer custom and prefab ADUs with transparent pricing and free on-site evaluations.

BuildShure specializes in ADUs and tiny homes, offering models like Studio Pod, Casita, and 2-bed Residence built with SIP Panels. They guarantee fixed pricing and pay $500/day for delays, ensuring reliable, energy-efficient backyard cottages.

The Springfield by Superior ADUs is a 2-bed, 2-bath detached ADU with open-concept living, vaulted ceilings, mini-split HVAC, kitchen island, ample storage, and optional ethanol fireplace—ideal as a granny flat or in-law suite.

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.

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.

Revival Homes is a California ADU project manager handling planning, financing, design, permitting, and construction. They build detached ADUs, garage conversions, JADUs, and more, with costs ranging from $100K to $300K.

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.

Los Angeles Advanced ADU Builders offers full-service ADU construction across LA, including garage conversions, detached units, JADUs & prefab ADUs. With 20+ years experience & 500+ builds, they handle design, permits & zoning compliance.

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.

MyADU4Less is a Southern California ADU builder specializing in prefabricated accessory dwelling units. Offering models from 160–1,200 sq ft, they handle design, permitting, and construction. CalHFA grants up to $40,000 may apply.