Basement Conversion in California

House to Home is a trusted ADU builder in San Diego with 25+ years of experience. They specialize in granny flats, guest houses, garage conversions, and Junior ADUs, serving San Diego, Carlsbad, La Jolla & more.

MHP Construction offers ADU construction services in California, including detached units, conversions, and in-law suites. ADUs provide rental income, family housing, and flexible living—without buying extra land.

Bartona Builders specializes in ADU construction in Los Angeles, offering detached ADUs, garage conversions, and in-law suites. They manage the full build process, ensuring code-compliant construction that adds value to residential properties.

A+ Construction & Remodeling is a top-rated ADU contractor in Greater Sacramento with 30+ years experience. They offer custom ADUs, garage conversions, granny flats & more, managing all permits and zoning compliance. CSLB Licensed #1007869... read more

ADU Builders Group is a Bay Area family-owned ADU contractor with 21+ years of experience. They build attached, detached, converted, and junior ADUs, offering full design-build services, permitting support, a 3-year warranty, and a 10-year structu... read more

Kaminskiy Home Remodeling builds ADUs in San Diego, including granny flats, garage conversions, JADUs & basement units. Boost property value, earn rental income, or house family. Serving Poway, La Jolla, Encinitas & more.

OakADU is a full-service ADU contractor in Los Angeles & Southern California, offering design, permitting, construction & property management for detached ADUs, garage conversions, attached ADUs & interior conversions.

Green Bee Construction Inc builds high-end ADUs, custom homes, additions, and renovations for Nevada County homeowners who want quality they can trust. Based in Grass Valley, we bring twenty years of local permitting expertise — including septic... read more

Golden State ADUs is a Sacramento-based full-service ADU contractor offering design, permitting & construction. With 10+ years experience and 100+ projects, they build detached ADUs, in-law suites & backyard cottages across California.

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.

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.

Delcoi is an ADU contractor specializing in granny flats, casitas, in-law suites, detached ADUs, garage conversions, and backyard cottages. They handle permits, regulatory compliance, and quality construction to maximize living space and rental in... read more

Backyard Unlimited, founded 2009 in Rocklin, CA, specializes in Amish-crafted sheds, gazebos, pergolas, and ADUs for Greater Sacramento homeowners. They handle full ADU design, permitting, and installation in-house, with no subcontractors.

Apex ADU Builders is a Los Angeles-based contractor specializing in accessory dwelling unit construction. Services include new builds, garage conversions, permitting, and design. Costs range from $80K–$400K, with potential ROI 35% higher than ho... read more

9 Builders is a Bay Area ADU contractor offering full-service design, permits & construction. Specializing in detached ADUs, garage conversions & additions, costs range $150K–$350K, taking 8–14 months to complete.