Accessory dwelling units are one of the most practical ways to add space and value to a Bay Area property. A backyard cottage can house a parent, an adult child or a tenant; a converted garage can become a full apartment. Ramos General Building builds ADUs across Oakland and the Bay Area, from the foundation to the final finishes.
ADU types we build in Oakland
- Detached ADUs. A separate small home in the backyard, built from the ground up like any new construction project.
- Attached ADUs. A unit added to the side or back of the main house, with its own entrance.
- Garage conversions. An existing garage rebuilt as a living unit, with new insulation, windows, a kitchen and a bathroom.
- Junior ADUs. A unit of up to 500 square feet created within the existing home, often from a bedroom with an added efficiency kitchen.
Oakland ADU rules to know before you plan
ADU rules come from both state law and the City of Oakland, and they change often. These are general guidelines; your lot, zoning and the current code set the final numbers:
- Size. Detached ADUs up to 1,200 square feet; attached ADUs up to 50% of the main home’s floor area; junior ADUs up to 500 square feet.
- Setbacks. Most new ADUs need 4 feet from the side and rear property lines. Converted structures that already sit closer may qualify for exceptions.
- Height. Detached ADUs are generally limited to 16 feet, with more height allowed in some cases.
- Parking. No replacement parking for garage conversions, and typically no parking requirement within half a mile of transit.
- Approval timeline. State law requires a decision within 60 days of a complete application.
- Fees. From 2026, ADUs of 750 square feet or less are exempt from development impact fees under state law.
How we build an ADU from start to finish
- Site visit. We look at the lot, access to the backyard, utilities and any existing structure. The estimate is free.
- Plans and engineering. Your designer or architect prepares plans; we review them for cost and constructability.
- Permits. Building permit review, plus the construction waste recycling plan that every Oakland permit requires.
- Foundation and framing. Built for the soil and the seismic design on the plans.
- Utilities and systems. Coordination of water, sewer and electrical connections, which are often the most site-specific part of an ADU.
- Finishes and walkthrough. Kitchen, bathroom, flooring and fixtures, then a full walkthrough with you.
Making a small unit live large
Good ADUs feel bigger than their square footage: high ceilings where the height limit allows, windows placed for light and privacy, storage built into walls and a kitchen sized for real cooking. The bathroom deserves the same care as any bathroom remodel, because in a small unit moisture has fewer places to go. If you need more room inside the main house instead, compare with a home addition.