California ADU rules · Riverside County
Can I Build an ADU in Hemet?
Yes — you can build an ADU in Hemet. California's statewide ADU law requires every city, including Hemet, 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
Local ruleUp to 2 detached ADUs, 1 attached ADU, and 1 JADU; total dwellings (primary + ADUs/JADUs) may not exceed 4 per lot
Units on a multifamily lot
Local ruleUp to 2 detached ADUs (proposed multifamily) or up to 4 detached ADUs (existing multifamily, subject to setbacks and not exceeding the number of primary units); up to 25% of existing multifamily units as attached ADUs (minimum 1); up to 25% of existing non-livable space converted to ADUs (minimum 1)
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 rule1,000 sq ft
1,000 sq ft for 2+ bedrooms; 850 sq ft for studio/1-bedroom. Detached ADUs meeting simplified approval standards may not exceed 800 sq ft.
Max attached ADU size
Local rule850 sq ft (studio/1-bedroom), 1,000 sq ft (2+ bedrooms), or 50% of the existing primary dwelling’s floor area if expanding by more than 150 sq ft (whichever is less)
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
16 ft for 1-story detached; 18 ft if within ½ mile of major transit or abutting multi-story multifamily; 25 ft for 2-story detached over garage or attached ADU (or primary dwelling height limit, whichever is less); +2 ft for matching roof pitch.
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
CA state lawNo front setback may block the mandatory 800 sq ft / 16-ft / 4-ft-setback ADU; otherwise per base zone
Separation from main house
CA state lawNone required
No statewide separation requirement between the ADU and the primary dwelling.
Parking
Parking required
Local ruleUp to 1 space
No parking required for ADUs/JADUs except for detached ADUs, where 1 space per unit or per bedroom (whichever is less) may be required; multiple exemptions apply.
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 off-street parking required when a garage, carport, or parking structure is demolished or converted to an ADU.
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 not required for ADUs. For JADUs, owner must reside in main home or JADU unless JADU has separate sanitation or is owned by a government/land trust/housing org.
Impact-fee waiver
Local ruleWaived under 750 sq ft
No impact fee for ADUs/JADUs <750 sq ft. School fee exemption for units ≤500 sq ft.
Permits required
CA state lawBuilding permit
Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.
Hemet-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
Sprinkler requirements
Fire sprinklers required in ADU only if required in the primary dwelling.
Hemet limits detached ADUs to 1,000 sq ft (2+ bedrooms) or 850 sq ft (studio/1-bed), and allows up to 2 detached plus 1 attached ADU and 1 JADU per single-family lot, with a maximum of 4 dwellings per lot. Height can reach 25 ft for 2-story ADUs over garages or attached units.
Frequently asked questions
Can I build an ADU in Hemet?
Yes. California's statewide ADU law requires Hemet 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 Hemet?
A detached ADU of at least 1,000 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 Hemet?
Side and rear setbacks are limited to 4 ft. No front setback may block the mandatory 800 sq ft / 16-ft / 4-ft-setback ADU; otherwise per base zone.
Is parking required for an ADU in Hemet?
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 Hemet?
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 Hemet?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- Hemet Municipal Code Sec. 90-321 (Ord. No. 2072, § 2, 3-10-26)
- Sec. 90-321(c)(3)
- Sec. 90-321(c)(7)
- Sec. 90-321(c)(6)
- Sec. 90-321(c)(15)-(17)
- Sec. 90-321(c)(11)-(12)
- Sec. 90-321(c)(11)
- Sec. 90-321(d)(5)
- Sec. 90-321(c)(13)-(14)
- Sec. 90-321(c)(18)
- 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 § 66333 (junior ADUs)
- Cal. Gov. Code § 66321 (size minimums & height)
- Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
- Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
Last updated 2026-06-25. This is an AI-assisted summary of Hemet'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 Hemet Planning before relying on it.
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