Can I Build an ADU in Anaheim?

Yes — by right

ADUs and JADUs are allowed by right in all residential and mixed-use zones; ministerial approval, no hearing.

1 conversion/inside-space ADU + 1 new detached ADU + 1 JADU (max 4 units/lot incl. primary)

Anaheim allows one ADU in existing/proposed single-family or accessory space, one new-construction ADU, and one JADU — but caps the total dwelling units on a single-family-zoned lot at four, including the primary dwelling.

Conversion ADUs (≥1, up to 25% of units) + up to 8 detached

Conversions of non-livable space (at least 1, or up to 25% of existing units) plus up to 8 detached ADUs on a lot with existing multifamily — never exceeding the number of existing units. JADUs are single-family only.

Allowed

Up to 500 sq ft. Anaheim allows a JADU within the existing single-family home OR attached to a newly constructed detached ADU — not only inside the existing home.

1,200 sq ft

Anaheim allows a detached ADU above the 800 sq ft state floor up to 1,200 sq ft (Table 38-A, subject to AMC § 18.04.080.020). 800 sq ft is the state-protected by-right floor, NOT Anaheim's detached-ADU maximum.

50% of the primary dwelling, but ≥850 sq ft (≥1,000 sq ft for 2+ bedrooms) is always allowed

800 sq ft

An 800 sq ft ADU must be allowed regardless of FAR/lot-coverage caps; a city also cannot cap an attached ADU below 850 sq ft (1,000 for 2+ bedrooms).

500 sq ft

18 ft

18 ft plus 2 ft for roof pitch for a detached ADU, or the height of the main dwelling, whichever is greater; attached ADUs follow the underlying zone. Transit corridors get the state 20-ft allowance.

4 ft

A city cannot require more than 4 ft side or rear setback; conversions of existing structures are exempt.

4 ft

Detached ADU may be no closer to the front line than the front-most wall of the main dwelling; garage/carport conversions may sit in the front setback, and the Planning Director may reduce the front setback where needed to fit an 800 sq ft ADU

10 ft

The 10-ft separation between a detached ADU and the main dwelling applies to ADUs OVER 800 sq ft (Table 38-A). The 800 sq ft by-right ADU and conversions of legally established structures are exempt from building-separation requirements. State law sets no separation.

Up to 1 space

Anaheim requires 0 spaces for a studio ADU and 1 space for an ADU with one or more bedrooms, subject to the state exemptions (½-mi of transit, within an existing structure, historic district, etc.). No parking is required for a JADU.

Yes — no parking required near transit & for conversions

No parking may be required within ½ mi walking distance of transit, in a historic district, for an ADU within an existing structure, within one block of car-share, or in certain permit-parking areas.

Not required

When a garage/carport is demolished or converted to build an ADU, replacement parking cannot be required.

Ministerial (by right)

No public hearing or discretionary design review for a qualifying ADU.

60 days

The agency must act within 60 days of a complete application — and the ADU is deemed approved if it does not.

Only for a JADU

No owner-occupancy for ADUs. Owner-occupancy is required for a JADU that shares sanitation facilities with the primary residence; Anaheim's checklist still routes applicants through a JADU owner-occupancy covenant, so confirm directly with Planning for a JADU with its own bathroom.

Waived under 750 sq ft

An ADU of 750 sq ft or less pays no impact fees (the 750 sq ft threshold itself is exempt under § 66311.5); larger ADUs pay fees proportional to the primary dwelling. JADUs (≤ 500 sq ft) are exempt.

Building permit

Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.