How big can a backyard cottage be in Long Beach?
As of October 2026, Long Beach reviews ADUs under state law while it prepares a new local ordinance. State law guarantees room for at least an 800 sq ft ADU with 4-foot side and rear setbacks. Where state standards apply in place of a compliant local ordinance, a new detached ADU can be up to 1,200 sq ft of interior living space.
The exact limit can depend on how the unit is combined with others on the lot. When a detached ADU is paired with a converted ADU and a junior ADU on one single-family lot, the city's bulletin lists the detached unit at up to 800 sq ft. We confirm the number for your lot before design starts.
How tall can a detached ADU be?
- 16 feet for most new detached ADUs.
- 18 feet within a half-mile walk of a major transit stop or high-quality transit corridor, plus up to 2 more feet for a sloped roof that matches the main home.
- 18 feet on a lot with an existing multi-story multi-family building.
Heights as of October 2026, from the City of Long Beach ADU bulletin. In PD-11 (Rancho Estates), the district limit is 13 feet and one story, but detached ADUs may still be at least 16 feet.
What setbacks apply?
For new construction, as of October 2026: 4 feet on the interior side and 4 feet at the rear. On an alley lot, the rear setback is measured to the alley centerline, which can free up useful yard space. Front and street-side setbacks follow the zoning district.
Utility easements and recorded restrictions can require more than 4 feet. We check your title report and survey for these early.
Will a backyard cottage need parking?
Often not. As of October 2026, Long Beach lists exemptions including a location within a half-mile of public transit, a historic district, or an on-street permit area where permits are not offered to the ADU occupant. The city notes that most Long Beach locations are exempt. Otherwise, the limit is one space per ADU, and it can be in an open driveway or tandem.
What fees apply to a detached ADU?
As of October 2026, state law bars impact fees on an ADU of 750 sq ft or less of interior living space. Larger units may be charged impact fees in proportion to their size. A utility may require a new or separate connection for a detached unit and charge a connection fee or capacity charge proportionate to its burden on the system.
Is my lot in the coastal zone?
Parts of Long Beach are. As of October 2026, a coastal zone ADU needs an Administrative Local Coastal Development Permit, filed with the building permit, with no public hearing. The city highly encourages at least one parking space per ADU there where feasible.
When is a backyard cottage the right choice?
It depends on your yard and budget. A cottage suits a lot with open rear space, good access for materials, and owners who want full separation from the tenant. If you have a sound garage, a garage conversion usually costs less. If the yard is tight, an attached ADU may fit better.
Related
Rules as of October 2026, from the City of Long Beach ADU bulletin (IB-PZ-001) and zoning summary, California Government Code §66311.5 and the HCD ADU Handbook.
See what fits on your lot
Send your address. We check setbacks, alley access, easements and overlays, then sketch what size cottage fits.