Riverside County
Cathedral City ADU rules
Research summary of local ADU rules on file for Cathedral City in Riverside County. Not a determination for a specific lot.
City or county ADU page
Check any California address for freeCathedral City rules on file
Local rules recorded in this project for this jurisdiction. Where a city figure on file is stricter than the state baseline on file, both are shown.
Which rules apply
Cathedral City's ADU rules are in Municipal Code Chapter 9.114, restated by Ordinance 897 (adopted March 25, 2026) to follow recent state law. The online code may not show this ordinance yet. Three items are left out of this summary because they may conflict with state law; state rules apply to those items.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Ord. 897 Sec. 1; Ch. 9.114, accessed 2026-10-25.
Review and timing
ADUs need a building permit, reviewed ministerially by the building “official” with no hearing. The City acts within 60 days of a complete application when there is an existing home on the lot (paused if you ask for a delay); with a new home, the ADU is acted on together with the new home. A garage demolition permit is issued with the ADU permit.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.030, accessed 2026-10-25.
Where ADUs are allowed
On a lot zoned for single-family or multifamily homes (by right or with a conditional use permit) that has an existing or proposed main home.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.050 (Zoning), accessed 2026-10-25.
How many units
Single-family lots: one junior ADU plus either one detached ADU of up to 800 sq ft and/or one conversion ADU, or one larger detached ADU or one attached ADU. Multifamily lots: conversions of non-living space up to 25% of the existing units (at least one); up to eight detached ADUs with an existing multifamily building (not more than the existing units) or two with a proposed one. No junior ADUs on multifamily lots.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.050 (Number of Units), accessed 2026-10-25.
Size limits
Minimum 150 sq ft. Detached ADUs over 800 sq ft: up to 850 sq ft (studio or one bedroom) or 1,000 sq ft (more than one bedroom), and no more than two bedrooms. Junior ADU: 150 to 500 sq ft inside the home.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Secs. 9.114.020, 9.114.100, accessed 2026-10-25.
Setbacks
Attached ADUs and detached ADUs: 4 ft side and rear; larger detached ADUs and attached ADUs use the zone's front setback. Conversions need no setbacks beyond fire and building code. Converted accessory structures may add up to 150 sq ft only for entry.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Secs. 9.114.060, 9.114.070, 9.114.090, 9.114.100, accessed 2026-10-25.
Height
Attached: the main home's height limit or 25 ft, whichever is lower, and no more than two stories. Detached: up to the main home's height, and at least 16 ft; 18 ft within a half mile of a major transit stop or high-quality transit corridor, or on a lot with a multistory multifamily building, plus 2 ft for a roof pitch that matches the main home.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Secs. 9.114.060, 9.114.090, 9.114.100, 9.114.120, accessed 2026-10-25.
Design and landscaping
Attached and larger detached ADUs must match the main home's design, materials, color and roofing, and new construction needs landscaping consistent with the main home and the City's water-efficiency rules (Chapter 8.57).
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Secs. 9.114.060, 9.114.100, accessed 2026-10-25.
Parking
Attached and larger detached ADUs need one parking space, which may be in setback areas or tandem. None is needed within a half mile walk of public transit, in a historic district, where on-street permits are not offered, within one block of a car share vehicle, or when the ADU is applied for with a new home. Garages or spaces removed for an ADU do not need to be replaced.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Secs. 9.114.050 (Parking), 9.114.060, 9.114.100, accessed 2026-10-25.
Entrance
Each ADU needs its own exterior entrance, separate from the main home.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Secs. 9.114.060, 9.114.070, 9.114.110, accessed 2026-10-25.
Junior ADUs
One junior ADU per single-family lot, inside the walls of the existing or proposed home (not in an accessory building), with its own exterior entrance and an efficiency kitchen. A recorded deed restriction bars selling it separately and limits it to 500 sq ft.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.080, accessed 2026-10-25.
Rentals and separate sale
An ADU may be rented but not sold separately from the main home except as Gov. Code 66340-66342 allow. ADUs may not be used as short-term vacation rentals (Chapter 5.96).
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.050 (Ownership and Occupancy), accessed 2026-10-25.
Fire sprinklers
Not required unless the main home needs them, and an ADU does not trigger sprinklers in the main home.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.050 (Building Codes), accessed 2026-10-25.
Sewer
ADUs connect to the public sewer unless an exemption is granted under Chapter 8.50; a private system must be sized to the building code.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.050 (Septic and Sewer), accessed 2026-10-25.
Impact fees
No impact fee for an ADU of 750 sq ft or less, including junior ADUs. Larger ADUs pay in proportion to the main home.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.030, accessed 2026-10-25.
Older unpermitted units
The City will not deny a permit for an unpermitted ADU or junior ADU built before 2020 for nonconforming zoning or building-standard violations unless it is substandard under Health and Safety Code 17920.3.
Source: City of Cathedral City Ordinance No. 897 (adopted March 25, 2026), Exhibit 1: Municipal Code Chapter 9.114 Accessory Dwelling Units, Sec. 9.114.030, accessed 2026-10-25.
Where to ask
Cathedral City Building and Safety. The City's “Pre-Approved” ADU Program page offers four free ADU plan sets and links Chapter 9.114.
Source: City of Cathedral City “Pre-Approved” ADU Program page, accessed 2026-10-25.
California state rules on file
The statewide baseline recorded from state law and the HCD ADU Handbook.
Detached size cap described in state law
1,200 sq ft. Recorded in this rules file from Government Code section 66314.
Source: California Government Code section 66314, 66314, accessed 2026-10-16.
Side and rear setback cap for a new ADU
4 ft. Recorded in this rules file from Government Code section 66314, which describes a cap on side and rear setbacks for a new ADU.
Source: California Government Code section 66314, 66314, accessed 2026-10-16.
Setback for a conversion of an existing structure
No additional setback, as recorded in this rules file from Government Code section 66314 for a conversion of an existing structure.
Source: California Government Code section 66314, 66314, accessed 2026-10-16.
Minimum lot size
A city may not impose a minimum lot size for an ADU, as recorded in this rules file from Government Code section 66314.
Source: California Government Code section 66314, 66314, accessed 2026-10-16.
Minimum unit the handbook says cities must allow
At least an 800 sq ft ADU with 4 ft side and rear setbacks. The HCD ADU Handbook (updated March 2026) describes this under section 66321(b)(3).
Source: HCD ADU Handbook, 66321(b)(3); handbook updated March 2026, accessed 2026-10-16.
Detached height described in the handbook
16 ft, or 18 ft or 20 ft in some cases. The HCD ADU Handbook (updated March 2026) describes this under section 66321(b)(4).
Source: HCD ADU Handbook, 66321(b)(4); handbook updated March 2026, accessed 2026-10-16.
Permit decision deadline
60 days. Recorded in this rules file from Government Code section 66317(a)(3): the permitting agency must decide on (approve or deny) a completed ADU application within 60 days when an existing single-family or multifamily dwelling is on the lot. Section 66317(a)(1) says the application is considered ministerially, without discretionary review or a hearing.
Source: California Government Code section 66317, 66317(a)(1), (a)(3), accessed 2026-10-17.
Owner-occupancy requirement
None. Recorded in this rules file from Government Code section 66315: a local agency may not impose an owner-occupancy requirement on an ADU. It may require that the property be used for rentals of terms 30 days or longer. The HCD ADU Handbook (updated March 2026) describes the same rule.
Source: California Government Code section 66315, 66315; HCD ADU Handbook updated March 2026, accessed 2026-10-17.
Parking near public transit
No parking standards within one-half mile walking distance of public transit. Recorded in this rules file from Government Code section 66322(a)(1). Section 66322(a) lists several other cases where parking standards may not be imposed.
Source: California Government Code section 66322, 66322(a), accessed 2026-10-17.
Ministerial categories
The HCD ADU Handbook (updated March 2026) states that Government Code section 66323 sets four ministerial categories. This rules file does not restate those four categories.
Source: HCD ADU Handbook, 66323; handbook updated March 2026, accessed 2026-10-16.
Fire Hazard Severity Zones
If your lot is in a Fire Hazard Severity Zone, the CAL FIRE Office of the State Fire Marshal says in Information Bulletin 25-004 (issued March 3, 2025): “Fire Hazard Severity Zones (FHSZs) should not restrict the development of Accessory Dwelling Units (ADUs). However, additional building standards may be necessary, including but not limited to California Fire Code Chapter 49 and California Building Code Chapter 7A.” State ADU law does not itself bar an ADU there. A city or county may still apply its building code, including wildfire-resistant construction (Gov. Code 66314(d)(8)); require side and rear setbacks “sufficient for fire and safety” for a unit converted under 66323(a)(1); and decline parking in setbacks on specific fire and life safety findings (66314(d)(10)(B)). It may also consider public safety when it designates where ADUs may be permitted (66314(a)). Sprinklers can't be required in an ADU or JADU if the primary residence doesn't need them (66314(d)(12), 66323(d)). Some cities and counties still apply their own fire-zone limits. Where this summary has one, it is listed with the local rules. This summary does not look up your lot. Check the CAL FIRE Fire Hazard Severity Zone map viewer linked from the State Fire Marshal's Fire Hazard Severity Zones page: https://experience.arcgis.com/experience/5065c998b4b0462f9ec3c6c226c610a9
Source: CAL FIRE Office of the State Fire Marshal Information Bulletin 25-004, page 4, issued March 3, 2025; Gov. Code 66314, 66323, accessed 2026-10-20.
State baseline on the directory → · State ADU rules on the homepage →
Can I build an ADU in Cathedral City?
State law sets a baseline for ADUs in Cathedral City, and the local standards on file are listed on this page. Whether a specific lot can add an ADU depends on zoning, utilities, and other site facts this page does not measure. Confirm with the City of Cathedral City Planning and Building Divisions, or run a free address summary.
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