Grass Valley, CA Accessory Structures: Tiny Homes (2026)

Nevada County is one of the few California counties to legalize Tiny Homes on Wheels (THOWs) for full-time living. On January 14, 2025, the Board of Supervisors adopted Ordinance ORD24-2, amending Title 12 (Zoning Regulations) of the Nevada County Code to allow THOWs as permanent housing. A THOW is defined as a moveable dwelling no larger than 400 sq ft that includes a kitchen, bathroom, and sleeping area, and is intended for permanent residential use, distinguishing it from a recreational vehicle (RV). Under the ordinance, THOWs may be used as single-family dwellings, second/secondary dwelling units, or accessory dwelling units. THOWs and ADUs are ministerially permitted, regardless of minimum parcel size and zoning density, on parcels within the RA (Residential Agricultural), R1, R2, AE, AG, FR (Forest), and TPZ (Timber Production) zoning districts, subject to zoning compliance and issuance of a building permit. Because THOWs must comply with zoning and building permit requirements, owners should confirm utility, water, sewer/septic, and anchoring standards with the Community Development Agency. The County has separately indicated that RV use as housing and temporary occupancy provisions will be revisited with revisions expected in 2026, so RV rules differ from the THOW rules.