What is a garage conversion ADU?
It is an accessory dwelling unit built inside an existing attached or detached garage. When finished, it is a complete home: an independent exterior entrance, a full bathroom and a full kitchen with a permanent cooking appliance, which is what Long Beach requires of an ADU.
An attached garage can also become a junior ADU of up to 500 sq ft, as of October 2026.
Do I have to replace the parking?
No. As of October 2026, California law (Government Code §66314(d)(11)) does not let a city require replacement parking when a garage, carport or covered parking is converted to an ADU. Long Beach confirms this in its ADU zoning summary.
One Long Beach detail: if the conversion leaves your driveway too short for a code-compliant or compact stall, the unused curb cut must be removed and the curb restored. Read more in our parking guide.
How big can a garage conversion be?
As of October 2026, Long Beach sets no size limit for a conversion, but the unit cannot exceed the existing building footprint. You may add up to 150 sq ft only for entry and exit, such as a stair or landing.
Can I keep the garage where it is, close to the property line?
Usually. Converted structures do not have to meet the 4-foot side and rear setback, as long as the existing setbacks are enough for fire and life safety as decided by the city's building and fire officials. Height inside a non-conforming setback area cannot increase.
What work does a garage usually need?
A garage was built to park cars, not for people to live in. The California HCD garage conversion guidelines list the common upgrades:
- Checking the foundation and walls, and sometimes underpinning or upgrading the slab.
- A moisture barrier between the slab and the new floor.
- Insulation that meets the California Title 24 energy code.
- Replacing the garage door with wall, windows or a door, with structural work for new openings.
- Fire-rated walls where the unit is close to the house or a property line.
- An electrical load calculation; many projects need a new main service and a subpanel.
- Upsized water, sewer or gas lines, and separate heating such as a ductless mini-split.
Will I need new utility connections?
As of October 2026, state law (Government Code §66311.5) says a utility cannot require a new or separate connection for an ADU created within existing space, or charge a related connection fee or capacity charge, unless the unit is built with a new single-family home. You may still choose separate meters. See our utility meter guide.
When does a garage conversion not make sense?
It depends on the structure. A garage with a failing slab, very low walls or major termite damage can cost almost as much to fix as to rebuild. Demolishing and rebuilding is allowed in Long Beach only when it is essential to the project. We inspect first and tell you which path is cheaper.
How much does a garage conversion cost?
It is usually the least expensive ADU type. National cost guides published in 2026 put garage conversions at roughly $50,000 to $150,000 before permits and fees, as of October 2026. Long Beach projects can land outside that range. See the Long Beach ADU cost guide.
Related
Rules as of October 2026, from the City of Long Beach ADU bulletin (IB-PZ-001) and zoning summary, California Government Code and HCD guidance.
See what fits on your lot
Send your address and tell us about the garage. We check setbacks, overlays and the structure before you spend anything on plans.