Riverside County Additional Residential Accommodations ("ARA")

Questions?

Please contact:

Riverside County Planning Department

(951) 955-3200

Email [email protected]

ARA STANDARDS (ADUs, JUNIOR ADUs, SECOND UNITs AND GUEST QUARTER)*

STANDARD	ADDITIONAL RESIDENTIAL ACCOMMODATION (ARA) TYPES (Additional table coming soon with Ranchets and MOG Standards)

Single Family	1 unit/lot	1 unit/lot
Multifamily	1 interior unit/lot (or a quantity that is ≤ 25% of existing multifamily units, whichever is greater)	N/A	2 units/lot	N/A	N/A

Kitchen	Full	Cooking appliance, prep. counters, & storage cabinets, at a minimum	Full	None allowed
Bathroom (Minimum)	Toilet, shower, sink	Toilet, shower, sink (may shared facilities with house permitted)	Toilet, shower, sink	Optional

Lot Size	Permitted on any lot size	> 7,200 s.f.	Permitted on any lot size
Lot Coverage	Set by zoning classification (ADU floor area not included in the calculation)
Setbacks, rear/side (Minimum)	4 feet (for addition)	4 feet	Per zoning
Floor Area (Maximum)	Floor area must be ≤ 50% of primary unit floor area (Max. floor area area allowed must be between 800 square feet (sf) to 1,000 sf)	≤ 50% of primary unit floor area (or 500 sf, whichever is less)	1,000 sf	Max. floor area depends on lot size: - up to 1,200 s.f. unit (7,201-20,000 s.f. lots); - up to 1,500 s.f. unit (20,000 s.f.-1.99 ac. lots) - up to 2,500 s.f. (2 ac.-3.99 ac. lots) - up to 200% of primary house area (4+ ac. lots)	2% of lot size (or 600 s.f, whichever is less)
Height	N/A (only in one story)	16 feet	No taller than primary unit	Per zoning
Parking (Replace- ment parking if existing space(s) are converted?)	Interior w/in existing struct./Junior ADU: None required (no replacement) Interior within new structure: See detached ADU	1 space/unit (no replacement) - regular or tandem spaces - may be waived	1 space for one-bedroom units; or 2 spaces for units with two or more units -regular or tandem spaces (replacement may be required)	None required (no replacement)

Review	60 days from complete application, if primary unit exists (Per Building Code, if primary unit is new)	Per Building Code
Occupancy	Owner does not need to live onsite	Owner must live onsite	Owner does not need to live onsite	Owner must live onsite

STANDARD

ADDITIONAL RESIDENTIAL ACCOMMODATION (ARA) TYPES
(Additional table coming soon with Ranchets and MOG Standards)

INTERIOR or ATTACHED

DETACHED

ADU

SECOND UNIT (SU)

Guest Quarter (GQ)

ACCESSORY
DWELLING
UNIT (ADU)

Junior ADU

Single Family

1 unit/lot

Multifamily

1 interior unit/lot
(or a quantity that is
≤ 25% of existing
multifamily units,
whichever is greater)

N/A

2 units/lot

N/A

Kitchen

Full

Cooking appliance,
prep. counters, &
storage cabinets,
at a minimum

Full

None allowed

Bathroom
(Minimum)

Toilet, shower, sink

Toilet, shower, sink
(may shared
facilities with
house permitted)

Toilet, shower, sink

Optional

Lot Size

Permitted on
any lot size

> 7,200 s.f.

Permitted on
any lot size

Lot Coverage

Set by zoning classification (ADU floor area not included in the calculation)

Setbacks,
rear/side
(Minimum)

4 feet (for addition)

4 feet

Per zoning

Floor Area
(Maximum)

Floor area must be
≤ 50% of primary unit
floor area (Max. floor area
area allowed must be
between 800 square
feet (sf) to 1,000 sf)

≤ 50% of primary
unit floor area
(or 500 sf,
whichever is less)

1,000 sf

Max. floor area
depends on lot size:

- up to 1,200 s.f. unit
(7,201-20,000 s.f. lots);

- up to 1,500 s.f. unit
(20,000 s.f.-1.99 ac. lots)

- up to 2,500 s.f.
(2 ac.-3.99 ac. lots)

- up to 200% of
primary house area
(4+ ac. lots)

2% of lot size
(or 600 s.f,
whichever
is less)

Height

N/A (only in one story)

16 feet

No taller than
primary unit

Per zoning

Parking
(Replace-
ment parking
if existing
space(s) are
converted?)

Interior w/in existing struct./Junior ADU:
None required (no replacement)

Interior within new structure:
See detached ADU

1 space/unit
(no replacement)
- regular or
tandem spaces
- may be waived

1 space for
one-bedroom units; or
2 spaces for units
with two or more units
-regular or
tandem spaces
(replacement
may be required)

None
required
(no replacement)

Review

60 days from complete application, if primary unit exists
(Per Building Code, if primary unit is new)

Per Building Code

Occupancy

Owner does not need
to live onsite

Owner must
live onsite

Owner does not need
to live onsite

Owner must live onsite

*Draft standards: the above standards may be amended from time to time to correct errors or update interpretations. Last updated: 9.24.20
PDF version: Standards Matrix (under revision)