Basement Conversion in California

JP Homes is a licensed ADU contractor in Southern California, serving Los Angeles, Orange County, Riverside & San Bernardino. They offer full-service ADU construction including detached units, garage conversions & more.

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.

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

American Builders is a San Francisco ADU contractor specializing in garage conversions, detached units, in-law suites & basement conversions. They handle permits, zoning, and deliver code-compliant accessory dwelling units on time and on budget.

Built Environment Inc. is a licensed Northern California ADU contractor with 20+ years of experience. They build detached, attached, internal, JADU, and garage conversion ADUs, guiding homeowners from consultation to completion per California building codes.

West Coast Building and Design builds ADUs in California, including granny flats, garage conversions, and detached units. They help homeowners boost property value, house family members, or earn rental income through structured, process-driven construction.

Streamline Design Group offers ADU design and permitting in San Diego, covering detached, attached, JADU, garage conversions, and multi-family units. Referenced in the State ADU handbook, they deliver permit-ready plans at 40–60% less than architect fees.

ExpandADU is a California-based prefab ADU builder offering full-service accessory dwelling unit construction, including consultation, design, planning, and build. Serving the Bay Area and beyond, they specialize in detached ADUs, granny flats, and JADUs.

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.

EHD Builders offers ADU construction services in Los Angeles, CA, including garage conversions, detached units & additions. Costs range from $150K–$350K+. Services cover permits, framing, plumbing, electrical & more.

Cozy ADU is a full-service ADU contractor in Greater Sacramento, CA, building detached ADUs, garage conversions, guest houses & more. Turnkey process from permits to construction. Free consultation available.

Licensed ADU contractor Full Steam Ahead Construction serves East Bay homeowners with custom accessory dwelling units, including garage conversions, backyard cottages & in-law suites. Serving Concord, Oakland, Berkeley & 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.

Building a granny flat (ADU) in San Diego can boost property value and ease housing needs. Detached ADUs up to 1,200 sq ft start at $250/sq ft. Fee waivers may save homeowners $14,000+. Rules apply regarding zoning, lot use, and size limits.

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.