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Chapter 17.294 — ADDITIONAL RESIDENTIAL ACCOMMODATIONS

2.01 acres—4 acre lots.

Riverside County Municipal Code · 2026-09 edition · updated 2026-09-27 · Riverside County

The maximum floor area shall not exceed two thousand five hundred (2,500)

square feet.

d.

Lots greater than four acres. The maximum floor area shall not exceed two hundred (200) percent of the primary one-family dwelling's floor area.

Guest quarter. The maximum floor area shall not exceed two percent of the gross lot size or six hundred (600) square feet, whichever is less.

MOG units. Floor area shall comply with Title 25 of the California Code of Regulations, as may be amended.

Ranchets. No maximum floor area. The minimum floor area shall be four hundred fifty (450) square feet, excluding patios, porches, garages, and similar structures.

E.

Height. Additional residential accommodations shall comply with the following:

Interior ADU and junior ADU. An interior ADU and junior ADU shall be created within one story or floor of the building.

Attached ADU and detached ADU. The maximum height shall be no greater than sixteen (16) feet.

Guest quarters. The maximum height shall be pursuant to the applicable zoning classification for the lot.

Second units. The maximum height shall be no greater than the height of the primary one-family dwelling.

F.

Parking. Off-street parking shall comply with chapter 17.188 of this title and the following:

Interior ADU within an existing structure, junior ADU, or guest quarter.

a.

No parking space(s) shall be required.

b.

No replacement parking spaces shall be required for conversion of any existing parking spaces, including garages, carports or marked spaces into an interior ADU or a junior ADU. Any conversion of existing parking space(s) into a guest quarter shall be replaced at a 1:1 ratio.

Interior ADU within a new structure, attached ADU, or detached ADU.

a.

One (1) regular or tandem parking space per unit shall be required; or

b.

Parking may be waived, if any of the following apply to the lot or unit:

i.

Within a half mile walking distance from transit, including bus stop or train station locations where the public may access buses, trains or any other forms of transportation that charge set fares, run on fix routes and are available to the public;

ii.

Within an architecturally or a historically significant district;

iii.

Within an area that requires on-street parking permits but are not offered to the new unit; or

iv.

Within one mile from a car share area.

c.

Parking may be located within required setbacks established by this title.

d.

No replacement parking spaces shall be required for conversion of any existing parking spaces, including garages, carports or marked spaces into an ADU.

Second unit.

a.

One parking space per one-bedroom unit shall be required; or

b.

Two parking space for units with two or more bedrooms shall be required.

c.

Any conversion of existing parking space(s) into a second unit shall be replaced at a 1:1 ratio.

MOG units. Parking spaces shall be provided pursuant to chapter 17.188 of this title, with the exception of the following criteria:

a.

Parking spaces shall be located immediately adjacent to each MOG unit; and,

b.

Parking spaces shall be developed using impervious surfaces.

Ranchets. Parking spaces shall be provided pursuant to chapter 17.188 of this title.

G.

Design.

Additional residential accommodations shall be compatible with the architecture of the primary one-family dwelling or multiple-family dwelling on the same lot and consistent with the surrounding neighborhood.

Attached and Interior additional residential accommodations shall have exterior access to the unit.

In accordance with Title 25 of the California Code of Regulations, as may be amended, MOG Units and Ranchets shall include any required opaque skirt entirely around the unit in order to screen the area between the ground level and the floor of the unit.

H.

Access.

All weather access for emergency vehicles shall be provided for any additional residential accommodation that is located more than one hundred fifty (150) feet from a public right-of-way.

All access roads for emergency vehicle or driveways that service an additional residential accommodation shall be at least twenty (20) feet in width and shall have a clear and unobstructed access to the public road.

I.

MOG unit specific development standards.

MOG units shall be located within individual and separate spaces, which may also include accessory structures or appurtenances attached thereto or used in conjunction therewith. Spaces shall only include one MOG unit.

a.

The minimum size of each space within the lot shall be two thousand five hundred (2,500) square feet.

b.

The minimum dimension of the space shall be thirty (30) feet in width and eighty (80) feet in depth.

c.

The minimum coverage of each space shall not exceed seventy-five (75) percent of the space area with structures, including the manufactured home unit, any attached or detached accessory structures, such as awnings, stairways, and ramps.

Separation of buildings or structures shall comply with Title 25 of the California Code of Regulations, as may be amended.

Walls and fences and landscaping.

a.

A chain link fence, or other similar material, shall be erected along the perimeter of the lot, except when prohibited in flood areas or similar situations.

i.

The fence shall be at least six feet in height.

ii.

The fence shall be screen by landscaping or other material.

b.

A chain link fence, or other similar fencing, at least three feet in height shall be erected between spaces on the lot. Landscaping may be used in lieu of required fencing between spaces on the lot.

Additional access requirements.

a.

MOG units shall be located no further than four hundred fifty (450) feet from a public dedicated and maintained road.

b.

MOG units shall be served by an all-weather access road or driveway, such as a class 2 base or a material capable of supporting emergency vehicles as approved by the fire department.

c.

No additional curb cuts, rear access or any other types of access for the lot shall be allowed, except where authorized by the Riverside County Transportation Department through the issuance of an encroachment permit connecting with a public right-of-way.

(Ord. No. 348.4926, § 12, 8-25-2020)

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