Cal-Nev-Ari Accessory Structures: ADU Rules Rules (2026)

Nevada Assembly Bill 283 (2021), codified at NRS 278.02391, preempts excessive local restrictions on accessory dwelling units in cities and urban counties over 25,000 population, including unincorporated Clark County. Clark County Code Title 30 Section 30.40 sets the ADU framework: one accessory dwelling unit (attached or detached) is permitted by right on most single-family residential lots (R-E, R-D, R-1, R-2) of sufficient size. Typical standards include a maximum size equal to 50 percent of the primary dwelling or 1,200 square feet (whichever is less), minimum 10-foot side and 15-foot rear setbacks for detached units, compliance with the IRC and IFC for habitable space, a separate kitchen and bathroom, and one additional off-street parking space unless the property is within half a mile of transit. Owner-occupancy cannot be required by ordinance under the state preemption, although HOAs may impose their own CCandR restrictions. ADUs may be rented for 30-plus days but are generally NOT eligible to operate as short-term rentals (under 30 days) in Clark County. Utility separation, septic/sewer capacity, and firewall ratings for attached ADUs are enforced at plan check. Permitting runs through Clark County Department of Building and Fire Prevention and requires a Zoning verification, building permit, and final inspection.