ADUs & Garage Conversions in Anaheim

Anaheim has put more effort than most Orange County cities into making ADUs easier to build, with its own ADU program, a catalogue of pre-approved plans and a fast-track review. IA Builders is a licensed California general contractor (CSLB #1124696) based in Culver City, and we design and build ADUs, junior ADUs and garage conversions in Anaheim. The first decision is which of the city's review paths fits your lot and the unit you want.

Types of ADUs we build

• Junior ADU. A smaller unit created within the existing house, with an efficiency kitchen and its own exterior entrance.
• Garage conversion. An attached or detached garage turned into a living unit.
• Attached ADU. A new unit built onto the main house.
• Detached ADU. A new freestanding unit, usually in the rear yard.

More about the options is on our ADU and garage conversion page.

Two ways to get an ADU approved in Anaheim

Standard review

Most ADUs, including every attached unit, junior ADU and custom design, go through the city's standard building permit process. Plans are submitted to the Building Division of the Planning and Building Department, and Planning staff review the ADU against the zoning code during the Building Division's plan check. The city publishes a submittal checklist on its ADU Anaheim page. State law generally requires a city to act on a complete ADU application within 60 days.

ADU Express

ADU Express is the city's fast track for detached ADUs on qualifying single-family lots. You check your address with the city's eligibility tool, choose a design from the pre-approved plan catalogue, get a meter spot report from Anaheim Public Utilities and send it with the plan number to Planning and Building staff. The city says qualifying projects can complete review in 1 to 3 days.

The trade-off is flexibility. The catalogue plans have already been reviewed by every city department, so they can't be modified, and attached ADUs and custom designs aren't eligible. A pre-approved plan works well when one of the designs fits your yard and your utilities as drawn. If you want a different floor plan, a unit that matches the house or a layout around an existing tree or slope, standard review is usually the better route. We help you compare the two before you commit.

Electrical service and Anaheim Public Utilities

Anaheim runs its own electric utility, and that shows up in almost every ADU. A new unit adds load, and many older Anaheim houses have electrical service sized for an era before air conditioning, induction ranges and EV chargers. When a load calculation calls for a larger service or a new meter, Anaheim Public Utilities issues a meter spot report for the meter location, and an electric utility inspector visits the site. ADU Express requires that report before submittal. We bring the utility in early because meter location and service size can decide where the unit goes on the lot.

ADUs in different parts of Anaheim

West Anaheim and other tract neighborhoods

Mid-century tract lots often have a detached garage at the back and some open yard, which makes them good candidates for a garage conversion or a detached unit. Converting a garage is often the most economical path, since the foundation, walls and roof already exist. We check the slab, framing and drainage first, and add insulation, windows and a proper entrance so the space works as a home rather than a garage with drywall.

The Colony and other historic districts

An ADU behind a historic home is possible in many cases, but a design that suits the street matters. When a historic property applies for a building permit, the city's historic preservation staff review the plans and make recommendations, and the Colony Design Guidelines guide design in that district. That generally points toward a custom unit under standard review rather than a catalogue plan.

Anaheim Hills

Sloped lots and homeowners associations shape ADUs in Anaheim Hills. State law prevents CC&Rs from prohibiting or unreasonably restricting an ADU on a single-family lot, though associations can still apply reasonable standards, so we plan for that review alongside the city's. Parts of Anaheim Hills are also in fire hazard severity zones, where a new unit generally has to meet the state's wildfire-resistant construction standards for roofing, vents, siding and windows.

Our ADU process

We visit the property, check eligibility for ADU Express, look at utilities, access and any historic or HOA review, and help you choose the type of unit. Then we finalize the design, coordinate the meter spot with Anaheim Public Utilities, submit the plans and build the unit through final inspection. Since ADU rules and the city's fees have been updated several times, we confirm what's in effect when your project starts. We work across the city, as described on our Anaheim service area page. To talk through an ADU on your lot, call (213) 816-6465 or use the form on this page.

Frequently asked questions

What is ADU Express in Anaheim?

A fast-track review for detached ADUs built from the city's pre-approved plan catalogue on qualifying single-family lots. The city says review can be completed in 1 to 3 days, but the plans can't be changed.

Can I modify one of Anaheim's pre-approved ADU plans?

No. The plans are approved as drawn. If you need changes, the ADU goes through standard review instead.

Can I convert my garage into an ADU in Anaheim?

Yes, garage conversions are one of the ADU types the city reviews. They go through standard review, and we check the structure and utilities before design.

Do I need a meter spot report for my ADU?

If the ADU needs a larger electrical service or a new meter, yes. Anaheim Public Utilities issues it, and ADU Express requires it before you submit.

Last reviewed October 2026