Your city or county sets the building code
Nevada has no statewide residential building code. Each city or county may adopt one, and where it has, that is the code the build must meet. Clark County, for example, applies the 2024 International Residential Code with Southern Nevada amendments to applications filed from January 11, 2026. So the first question on any parcel is which building department covers it and which edition it has adopted.
Source: NRS 278.580 ; Clark County Building & Fire Prevention, Codes