ADU Rules in Los Angeles, CA (2026)

Los Angeles, CA permits accessory dwelling units (ADUs) on residential properties. ADUs — also called granny flats, in-law units, backyard cottages, or secondary suites — are secondary housing units on a single-family or multifamily lot. California state law actively preempts local restrictions, making ADU approval a streamlined ministerial process. In Los Angeles, the LA Department of Building and Safety (LADBS) handles ADU permit applications. Below you will find the current size limits, setbacks, fees, and timeline for building an ADU in Los Angeles.

ADU Size Limits

ADU Size Limits in Los Angeles: Detached ADU: up to 1200 sq ft (max height: 16 feet). Attached ADU: 50% of primary dwelling up to 1200 sqft. Junior ADU (JADU): up to 500 sq ft — must be within the existing primary dwelling or accessory structure. Detached ADU maximum is 1,200 sqft per California Gov Code 65852.2(c)(2)(B). JADU must be within existing or proposed space of a single-family dwelling or accessory structure. Garage conversion ADUs are limited to existing structure footprint plus 150 sqft for ingress/egress per Gov Code 65852.2(e)(1)(A).

Permit Fees

ADU Permit Fees in Los Angeles: Plan check fee: Varies by project value — typically $500–$3,000 for standard ADU. Building permit fee: Varies by valuation — typically $1,500–$5,000. Impact fees: None. School fees: Exempt per Gov Code 65852.2(f)(3) for ADUs under 750 sqft. ADUs 750+ sqft subject to school developer fees at $4.08/sqft (residential rate).. Total estimated permit cost: $2,000–$8,000 total permit fees depending on size and valuation. Impact fees (park, transportation, etc.) waived for ADUs under 750 sqft per Gov Code 65852.2(f)(3). City of LA also waives LADBS permit fees for ADUs under 500 sqft on affordable housing projects. Fee schedule: https://www.ladbs.org/permits/permit-fees

Permit Timeline

Los Angeles ADU Permit Timeline: Ministerial approval required within 60 days for ADU/JADU applications that comply with objective standards per Gov Code 65852.2(a)(3). LADBS ADU Express service targets 2-4 weeks for plan check. Construction typically 4-12 months depending on project scope. Apply through the LA Department of Building and Safety (LADBS) online permit portal. Phone: (213) 482-0000.

Setback Requirements

ADU Setback Requirements in Los Angeles: Front setback: Same as zone standard. Side setback: 4 feet. Rear setback: 4 feet. State law requires no setback for ADU that replaces existing structure in same location and footprint. 4-foot side and rear setbacks required for new detached ADUs per California Gov Code 65852.2(c)(2)(E). Front setback follows applicable zone standards.

Parking Requirements

Parking Requirements: No additional parking required for ADUs within one-half mile of public transit, within architecturally and historically significant historic districts, or when garage/carport is converted to ADU. Per California Gov Code 65852.2(d)(1)(A).

Restrictions & Requirements

• •ADU must comply with objective zoning and design standards
• •Setback violation structures may be rebuilt as ADU in same footprint per state law
• •ADU cannot be sold separately from primary dwelling (unless SB 9 lot split applies)
• •Short-term rental of ADU (less than 30 days) requires Home Sharing registration
• •ADU must have permanent foundation — no recreational vehicles or manufactured homes without permanent foundation

How Many ADUs Are Allowed?

Number of ADUs Allowed in Los Angeles: Single-family lots: 1 ADU + 1 JADU per single-family lot. Multifamily properties: Up to 25% of existing units (minimum 2) as detached ADUs; 1 ADU per existing unit for internal conversions. Per Gov Code 65852.2(e)(1)(B): multifamily properties may convert 25% of existing units to ADUs. One detached ADU permitted per multifamily lot per Gov Code 65852.2(e)(1)(C). SB 9 Urban Lot Split permits 2 units per parcel after qualifying lot split.

State Law & Preemption

Historic District Considerations

Frequently Asked Questions