California ADU rules · Riverside County
Can I Build an ADU in Wildomar?
Yes — you can build an ADU in Wildomar. California's statewide ADU law requires every city, including Wildomar, to approve a qualifying accessory dwelling unit by right, plus a junior ADU (JADU) on a single-family lot. What varies city to city are the local specifics below.
Can you build one?
ADUs allowed
CA state lawYes — by right
ADUs and JADUs are allowed by right in all residential and mixed-use zones; ministerial approval, no hearing.
Units on a single-family lot
CA state law1 ADU + 1 JADU
At least one ADU and one JADU per single-family lot (a conversion ADU may also be possible).
Units on a multifamily lot
Local ruleconversions (>=1 or 25% of units) + up to 2 detached
Local cap of 2 detached ADUs on multifamily lots, not 8 as in state default.
Junior ADU (JADU)
CA state lawAllowed
Up to 500 sq ft, within the walls of an existing single-family home (single-family lots only).
Size & height
Max detached ADU size
Local rule1,200 sq ft
Local maximum for detached ADUs is 1,200 sq ft.
Max attached ADU size
Local rule50% of primary dwelling floor area (must allow at least 850/1,000 sq ft per state)
Attached ADU may not exceed 50% of primary, but state minimums still apply.
Guaranteed minimum size
CA state law800 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).
Max JADU size
CA state law500 sq ft
Max height
Local rule25 ft
Local maximum height for ADUs is 25 ft.
Setbacks
Side setback
CA state law4 ft
A city cannot require more than 4 ft side or rear setback; conversions of existing structures are exempt.
Rear setback
CA state law4 ft
Front setback
Local rule20 feet minimum
Local front setback minimum is 20 ft.
Separation from main house
Local rule10 ft
10 ft minimum separation required between ADU and any other structure.
Parking
Parking required
Local ruleUp to 1 space
1 off-street parking space per ADU or per bedroom, whichever is less.
Transit parking exemption
CA state lawYes — 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.
Garage-conversion replacement parking
Local ruleNot required
No replacement parking required for garage/carport conversions.
Approval, timeline & cost
Approval path
CA state lawMinisterial (by right)
No public hearing or discretionary design review for a qualifying ADU.
Approval timeline
CA state law60 days
The agency must act within 60 days of a complete application — and the ADU is deemed approved if it does not.
Owner-occupancy
Local ruleOnly for a JADU
Owner-occupancy required only for JADUs.
Impact-fee waiver
CA state lawWaived 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.
Permits required
CA state lawBuilding permit
Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.
Wildomar-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
VHFHSZ emergency access
ADUs >150 ft from public right-of-way must provide all-weather emergency vehicle access per Riverside County Fire Dept.
Topography exception
ADU may be located in front yard if rear/side placement is impractical due to topography.
Wildomar limits detached ADUs on multifamily lots to 2, sets a 1,200 sq ft max for detached ADUs, requires 10 ft separation from other structures, and mandates a 20 ft front setback. Owner-occupancy is required only for JADUs.
Frequently asked questions
Can I build an ADU in Wildomar?
Yes. California's statewide ADU law requires Wildomar to approve a qualifying accessory dwelling unit ministerial (by right), plus a junior ADU (JADU) on a single-family lot.
How big can an ADU be in Wildomar?
A detached ADU of at least 1,200 sq ft must be allowed, and an ADU of 800 sq ft can never be zoned out by floor-area or lot-coverage limits. A JADU can be up to 500 sq ft.
What are the setback requirements for an ADU in Wildomar?
Side and rear setbacks are limited to 4 ft. 20 feet minimum.
Is parking required for an ADU in Wildomar?
Up to 1 space. No parking can be required within ½ mile of transit, for conversions, or for units inside the primary home. When a garage is converted, replacement parking is not required.
How long does ADU approval take in Wildomar?
A complete application must be acted on within 60 days, with ministerial (by right) — no public hearing or discretionary design review for a qualifying ADU.
Do I have to live on the property to build an ADU in Wildomar?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- Wildomar Municipal Code, Chapter 17.195 (Ord. 247, 1/15/2025; Ord. 256, 11/12/2025)
- §17.195.020; §17.195.060
- §17.195.050(B)
- §17.195.050(C)
- §17.195.050(A)(2)(d)
- §17.195.050(A)(2)
- §17.195.050(A)(1)
- §17.195.050(D)-(E)
- §17.195.050(D)(4)
- §17.195.060(B)
- §17.195.050(M)
- §17.195.050(L)
- Cal. Gov. Code §§ 66310–66342 (ADU Law)
- HCD 2025 Accessory Dwelling Unit Handbook
- Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)
- Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
- Cal. Gov. Code § 66333 (junior ADUs)
- Cal. Gov. Code § 66321 (size minimums & height)
- Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
- Cal. Gov. Code § 66311.5 (impact fees: none for an ADU ≤ 750 sq ft or JADU ≤ 500 sq ft)
Last updated January 15, 2025; November 12, 2025. This is an AI-assisted summary of Wildomar's ADU rules, drawn from its published ordinance and California ADU law — general information, not legal advice, and it may be incomplete or out of date. Verify the controlling rule for your specific parcel with Wildomar Planning before relying on it.
Will an ADU work on your Wildomar lot?
Ask GoCodebook about your address and get the size, setback, parking and permit rules that actually apply to your parcel — with the exact citation.
Check my parcel free