Everything homeowners ask about building an ADU in Long Beach — answered with 2026 data.
Yes, ADUs are allowed in All residential zones; R-1, R-2, R-3, R-4 and planned development zones in Long Beach, CA. The maximum size for a detached ADU is 1,200 sq ft. Attached ADUs can be up to 1,200 sq ft or 50% of primary dwelling. Long Beach has an ADU-friendliness score of 8/10. Check our full Long Beach ADU rules page for complete zoning details.
ADU construction in Long Beach typically costs $120,000-$280,000. The cost per square foot averages $180-$330. Garage conversions are more affordable at $70,000-$150,000, while prefab ADUs cost $90,000-$220,000. Permit fees add $3,000-$10,000 to your budget. See our detailed Long Beach ADU cost guide.
Detached ADUs in Long Beach can be up to 1,200 sq ft. Attached ADUs are limited to 1,200 sq ft or 50% of primary dwelling. Junior ADUs (JADUs) have a cap of 500 sq ft. Maximum height is Detached: 16 ft base (18 ft near transit, on multifamily lots, or built with a new primary dwelling; +2 ft to match roof pitch). Attached: up to 25 ft, matching a two-story primary dwelling. You are allowed up to 1 ADU + 1 JADU on a qualifying lot.
Rear setback: 4 ft. Side setback: 4 ft. Front setback: Per underlying zone. Note that garage conversions may be exempt from setback requirements if the existing structure is already within the setback area.
No parking required when within 1/2 mile of transit, for conversions, or other state exemptions; otherwise state law allows up to 1 space per ADU or per bedroom, whichever is less. Many cities and states have been relaxing ADU parking requirements in recent years. In California, no additional parking is required for ADUs near transit.
Not required. Note that owner-occupancy rules vary by state law — California and several other states have eliminated this requirement for standard ADUs.
The ADU permit review timeline in Long Beach is typically 60 days; often 30-45 in practice. Plan check: Efficient review process. Pre-approved plans availability: Yes — city has pre-approved ADU plans.
Average ADU rental income in Long Beach: 1-bedroom units rent for $1,500-$2,100/month, 2-bedroom units for $1,900-$2,700/month. Short-term rentals: Allowed with business license; STR regulations apply. Expected ROI: 7-11% annual return.
The minimum lot size for an ADU in Long Beach is No minimum. This applies to detached ADUs — garage conversions and JADUs may have different or no lot size requirements.
Garage conversions are one of the most popular and affordable ADU options. In Long Beach, a garage conversion typically costs $70,000-$150,000. The key advantages are lower cost (no foundation work), potential setback exemptions, and faster permitting. Read our complete garage conversion guide.