Prefab / Modular ADU near Orange, CA

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.read more

Ultra-Unit Architectural Studio, based in Long Beach, CA, offers architecture and construction services for ADUs, residential, multifamily, and commercial projects. Led by Cameron Crockett AIA, LEED, with 25+ years experience. Free initial consult... read more

A1 ADU Contractor specializes in garage conversions and custom ADU construction throughout Los Angeles and the San Fernando Valley. With over 15 years of experience, our team provides complete design, permitting, and construction services to trans... read more

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.

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.

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 construc... read more

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.

NewGen Tiny Homes, a family-owned ADU builder in Los Angeles, CA, designs and constructs custom tiny homes, detached ADUs, and backyard cottages. Insured and bonded, they guide clients from design through construction, maximizing property value an... read more

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.

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.

Clever Tiny Homes, based in Rialto, CA, manufactures factory-built tiny homes for ADUs, backyard cottages, and granny flats. Featuring quartz kitchens and modern design, homes are built in 12 weeks with financing and delivery support included.

USModular Inc. is a Temecula, CA ADU builder specializing in modular, prefabricated construction. Units are up to 90% factory-built, completed in ~120 days, and comply with IRC and local codes. Services include feasibility studies, design, enginee... read more

BSPK Design is a Venice, CA residential studio founded by Chris Faulhammer & Roman Reiterer, with 50+ years combined experience. Services include custom homes, fire rebuilds & prefab NextGen Building. Multiple Houzz Best of Design award wi... read more

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.

Lifescape Builders Inc provides ADU construction services in Temecula and Riverside County, including detached ADUs, granny flats, in-law suites, casitas, garage conversions, and JADUs, with customizable layouts, finishes, and full custom build op... read more