5 county-level rules, plus city-specific rules for 6 cities in Riverside County, California.
Verified from official government sources
Riverside County must allow Accessory Dwelling Units (ADUs) and Junior ADUs (JADUs) on any residential or mixed-use parcel under California Government Code §65852.2 and §65852.22. County Ord. 348 was updated to conform, and recent state laws (SB 1211, AB 2533) expand the number of detached ADUs allowed on multifamily sites.
Detached sheds and accessory buildings up to 120 square feet and under one story do not require a building permit in unincorporated Riverside County under the California Building Code, but all sheds must still comply with Ord. 348 zoning setbacks, typically 5 feet from side/rear property lines.
Converting a garage into habitable space in unincorporated Riverside County requires a building permit and typically a conversion ADU application. California ADU law (Gov Code §65852.2) requires the County to ministerially approve garage conversions to ADUs and waives the replacement-parking requirement.
Carports in unincorporated Riverside County require a building permit if they are attached to the dwelling or if their projected roof area exceeds 120 sq ft. Zoning setbacks under Ord. 348 apply, and any carport that encroaches into a side yard must be open on at least two sides and meet fire separation standards.
Tiny homes on permanent foundations under 500 sq ft may be permitted as Junior ADUs in unincorporated Riverside County. Tiny homes on wheels (THOWs) are treated as recreational vehicles under California law and cannot be used as permanent dwellings except in designated RV parks or under California's Movable Tiny House standards.
6 cities in Riverside County have their own accessory structures rules. Each link goes to that city's dedicated page with code citations.
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
5 verified rules • ADU Rules, Carport Rules
5 verified rules • ADU Rules, Carport Rules
5 verified rules • ADU Rules, Carport Rules
5 verified rules • ADU Rules, Carport Rules
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