Attached ADU near Downey, CA

Building an ADU in Riverside takes 8–16 months. JDB Builders guides homeowners through design (1–3 months), permitting (2–4 months), construction (4–8 months), and final inspections (1–2 months) for granny flats, garage conversions, and more.

iHome Design & Remodel specializes in custom ADU and casita construction, offering full-service builds from design to completion. Services include garage conversions, detached ADUs, permit handling, and free 3D consultations for homeowners.

Green Tech Remodeling offers full-service construction, renovation, and ADU projects including garage conversions, kitchen and bathroom remodels, home additions, flooring, roofing, electrical, plumbing, and more, with 3D design previews included.

Pasadena Master ADU Builder is a top ADU contractor in San Gabriel Valley, offering detached ADUs, garage conversions, and JADUs. With 20+ years experience, 150+ projects, and 98% satisfaction, they deliver compliant, high-quality builds boosting property value by 20–30%.

Golden ADU, serving Southern California since 2021, specializes in custom ADU construction including garage conversions and detached backyard cottages. They offer flexible financing with no upfront costs, completing most projects in 6–12 months.

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.

R Remodeling is a trusted ADU contractor in Whittier, specializing in accessory dwelling units for added living space or rental income. Experienced in detached ADUs, they manage projects from consultation to completion with minimal property disruption.

Potato Construction Inc., based in Rosemead, CA, is a licensed ADU contractor with 15+ years of experience. They build detached ADUs, garage conversions, attached ADUs, and JADUs across the San Gabriel Valley and greater Los Angeles area.

Romano Builders specializes in ADU construction in Los Angeles, offering detached, attached, garage conversion, and junior ADUs. Costs range $300–$600/sq ft, with rental income potential of $1,500–$4,000+/month.

Long Beach Elite ADU Solutions specializes in ADU construction and garage conversions in Long Beach, CA. Services include detached ADUs, JADUs, basement and above-garage units. 15+ years experience, 150+ completed projects.

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.

Saunders Construction Renovation Inc offers ADU construction in Torrance, Redondo Beach & Palos Verdes Peninsula. Services include detached ADUs, garage conversions & granny flats. BBB A+ rated South Bay contractor.

Coastal Builders is a Long Beach, CA ADU contractor specializing in detached, attached, garage conversion, basement, and attic ADUs. They offer design consultation, ADA-compliant builds, and custom units like granny flats and in-law suites.