An owner decision guide

Choose the Anaheim ADU type before choosing the floor plan

Detached, attached, conversion, and junior units solve different owner needs. Compare independence, site fit, existing-condition risk, utility routes, and the City pathway together.

Information reviewed September 5, 2026. Verify current rules with the linked public agency before relying on a detail.

The best project type is the one whose constraints match the property and intended use.

Project typeGood starting signalEarly constraintTypical City path
Detached ADUUsable yard area and a need for separationPlacement, access, utilities, building separation, site workStandard, catalogue, or Express if eligible
Attached ADUA logical addition zone connected to the homeStructural tie-in, privacy, roof and foundation coordinationStandard review
Garage conversionA legally established shell in a useful locationExisting slab, framing, moisture, fire and utility conditionsStandard review
JADUA compact program fitting within qualifying home spaceSize, interior relationship, owner occupancy and covenantStandard JADU review
AI design concept showing an attached Anaheim accessory dwelling unit connected to the main residence
AI design concept · Not completed workAttached ADU relationship study
AI design concept of a compact Anaheim junior accessory dwelling unit interior with kitchen and dining area
AI design concept · Not completed workJADU interior study

Anaheim identifies three approval approaches overall: standard review, use of a pre-approved plan, and ADU Express for qualifying properties. Read the City overview ↗

Five filters

Ask these before comparing elevations

Who will use it?

Long-term household use, aging needs, rental goals, privacy, accessibility, and daily circulation can point toward different building relationships.

Where can it fit?

Map setbacks, existing buildings, open space, access, grade, easements, trees, utilities, and emergency response before selecting a footprint.

How independent?

Detached construction offers physical separation. Attached and conversion projects may conserve yard but need closer privacy and shared-building coordination.

What is truly existing?

A conversion or addition depends on reliable records and field conditions. Unverified existing work is a scope risk, not automatic savings.

Which path fits?

A City pathway follows the property and proposal. Express eligibility or a catalogue plan should not dictate a type that fails the owner’s real needs.

What stays flexible?

Separate must-have program needs from finishes and options. Early flexibility helps the team respond to site findings without losing the project’s purpose.

Decision output

Shortlist two types, with one reason for and against each.

Add the property facts that would resolve the choice: legal records, a utility route, a structural observation, an eligibility result, or a site measurement. That creates a useful investigation plan instead of a preference contest.

Use the guided project planner →
Check feasibilityRead Anaheim’s current requirement categories