Garage Conversion in Anaheim, CA: Cost, Permits & Rules (2026)

A garage conversion is usually the lowest-cost path to an ADU in Anaheim — $90,000-$200,000, versus $220,000-$450,000 for a new detached build — because the shell already exists.

Garage Conversion Cost in Anaheim

Converting an existing garage in Anaheim runs $90,000-$200,000. That's well under the $220,000-$450,000 typical cost of a ground-up detached ADU, because you're reusing the foundation, walls, and roof. The biggest variables are whether the slab and framing are sound, what utility/electrical upgrades are needed, and your finish level. Permit fees add Building Permit Fees schedule (Exhibit A, Tier 3 Type VB, Residential Category 1, Dwellings and Custom; posted Aug 2026): combined plan check and building permit of $1,677 for the first 500 sq ft plus $213 per extra 100 sq ft up to 1,000 sq ft (about $2,316 for an 800 sq ft ADU), then $2,741 at 1,001 sq ft plus $171 per 100 sq ft (about $3,083 for 1,200 sq ft). Add trade permits (electrical $26 for the first 100 sq ft plus $0.26 per sq ft; plumbing $49 per fixture; $188 minimum per trade permit), Zoning Plan Check $352 and a $114 address fee (Planning fee schedule, Aug 2025). Budget roughly $3,000-$4,500 in city fees for an 800-1,200 sq ft detached ADU before impact and school fees. A converted unit rents for about $2,000-$2,700/mo (1BR) in Anaheim.

The Anaheim Garage Conversion Permit Process

A garage-to-ADU conversion in Anaheim needs building permits even if the exterior is unchanged. Approval process: Ministerial: the Planning and Building Director checks the plans against 18.38.015 under Gov. Code 66317 with no hearing, and no waiver, administrative adjustment or variance from the ADU standards may be approved or even accepted for filing (18.38.015.150, .1506). Three routes: 1) standard Building Division plan check with your own designer, 2) one of the city's free pre-approved plans run through standard plan check, or 3) ADU Express for eligible single-family lots (detached, catalogue plan only). Before submitting, get a sewer-capacity letter from Public Works (PWPermits@anaheim.net, up to four days), a free meter-spot report from Anaheim Public Utilities (714-765-6847, two to three business days) and a new address from the Permit Assistance Center (Nov 2025 ADU Submittal Requirements Checklist). Standard submittals take five sets of 24 x 36 plans at the City Hall Building counter (ADU FAQ 14); ADU Express is fully electronic. An appeal of a staff decision must be decided within 60 days (18.38.015.1505) The review timeline is The city must tell you within 15 business days whether the application is complete, each resubmittal gets the same 15-business-day check, and a complete application must be approved or denied within 60 days (18.38.015.1502 to .1504); under Gov. Code 66317(a)(3) as amended by SB 543 (Jan 1, 2026) an application not acted on in 60 days is deemed approved. If the ADU is filed with a permit for a new house, the ADU decision may wait for that permit. ADU Express: review in one to three days and the building permit issued in as little as one day after fees are paid, but the address-eligibility screening beforehand can take a few weeks (city ADU Express and catalogue pages). The Building Division publishes no standard plan-check turnaround, with plan check: Planning reviews zoning compliance inside the Building Division's plan check; plans must meet the 2025 California Building, Residential, Electrical, Mechanical, Plumbing, Energy, Fire and Green Building codes with Anaheim's Title 15 amendments for submittals on or after Jan 1, 2026 (Seismic Design Category D-F, Climate Zone 8). Fire sprinklers are not required in the ADU or JADU if the main house has none (18.38.015.0602). Even a free pre-approved plan may still need a site plan, Title 24 energy forms, structural details and a soils report from a design professional; the catalogue's Notes column says which. Pre-approved plans: Yes. The city's Pre-Approved Plan Catalogue lists four free detached plans (Sept 2026): Plan 001 studio 224 sq ft, Plan 002 one-bedroom 499 sq ft, Plan 003 two-bedroom 990 sq ft and Plan 004 three-bedroom 1,199 sq ft, all updated to the Building Code requirements effective July 1, 2024; no prefab or modular plans are listed yet. The plans may be used in standard plan check or through ADU Express, where they cannot be modified and conversions, expansions and attached ADUs are not eligible. Check eligibility by address with the ADU Express Eligibility Tool, then email ADUExpress@anaheim.net with the plan number and meter-spot report.

1. Confirm eligibility — ADUs are allowed in Every zone that allows single-family or multifamily residential use (AMC 18.38.015.010): RH-1, RH-2, RH-3, RS-1, RS-2, RS-3 and RS-4 (Table 4-B) and RM-1, RM-2, RM-3, RM-3.5 and RM-4 (Table 6-B), plus other zones where accessory to an existing legal home. A JADU needs a lot with an existing or proposed single-family house. Not allowed on a parcel that has used both an SB 9 two-unit development and an urban lot split (18.38.015.0502, 18.38.255.070), or in any area the City Council designates by resolution as lacking sewer capacity (18.38.015.0501); Public Works confirms sewer capacity by letter before plan check.
2. Prepare conversion plans — layout, egress windows, insulation, ventilation, smoke/CO detectors, plus a kitchen and bathroom.
3. Submit for plan check — Planning reviews zoning compliance inside the Building Division's plan check; plans must meet the 2025 California Building, Residential, Electrical, Mechanical, Plumbing, Energy, Fire and Green Building codes with Anaheim's Title 15 amendments for submittals on or after Jan 1, 2026 (Seismic Design Category D-F, Climate Zone 8). Fire sprinklers are not required in the ADU or JADU if the main house has none (18.38.015.0602). Even a free pre-approved plan may still need a site plan, Title 24 energy forms, structural details and a soils report from a design professional; the catalogue's Notes column says which.
4. Pull permits and build — fees run Building Permit Fees schedule (Exhibit A, Tier 3 Type VB, Residential Category 1, Dwellings and Custom; posted Aug 2026): combined plan check and building permit of $1,677 for the first 500 sq ft plus $213 per extra 100 sq ft up to 1,000 sq ft (about $2,316 for an 800 sq ft ADU), then $2,741 at 1,001 sq ft plus $171 per 100 sq ft (about $3,083 for 1,200 sq ft). Add trade permits (electrical $26 for the first 100 sq ft plus $0.26 per sq ft; plumbing $49 per fixture; $188 minimum per trade permit), Zoning Plan Check $352 and a $114 address fee (Planning fee schedule, Aug 2025). Budget roughly $3,000-$4,500 in city fees for an 800-1,200 sq ft detached ADU before impact and school fees; then framing, electrical, plumbing, and final inspection.

No Replacement Parking Required

No. California law (AB 68 / Gov Code §66314) prohibits cities from requiring replacement parking when you convert or demolish a garage to build an ADU — so you do not need to add a parking space anywhere on the lot. Owner-occupancy is not required, so you can rent the converted unit out.

The JADU Option for an Attached Garage

If your garage is attached to the house, you can convert it into a junior ADU (JADU) — capped at 500 sq ft maximum, 150 sq ft minimum, built within the walls of the existing or proposed single-family house or attached to a newly built detached ADU (18.38.015.0303, Ord. 6620). Up to 150 sq ft may be added to the house for entry and exit as long as the JADU stays at or under 500 sq ft; it needs an efficiency kitchen and its own exterior door, and may share a bathroom with the house if there is interior access (Table 38-A) and built within the existing walls. JADUs are cheaper and faster to permit than a full ADU, though they may share sanitation with the main home. A full ADU gives you more size and a separate unit; a JADU is the budget route.

Anaheim Garage Conversion FAQ