Santa Clara County, CA Accessory Structures: Tiny Homes (2026)

In 2020 the Santa Clara County Board of Supervisors amended the Zoning Ordinance to recognize Movable Tiny Homes (MTHs) as a legal form of accessory dwelling unit in unincorporated areas. Section 4.10.015(E) allows one movable tiny home per lot in lieu of one standard ADU. A movable tiny home must adhere to all the setback, height and floor-area limitations that apply to detached ADUs under Section 4.10.015(D), meaning a maximum living area of 1,200 square feet, at least four-foot side and rear setbacks, and a 16-foot height limit where single-family setbacks are not met. The unit must be a self-contained structure that complies with all State of California requirements, is built to the American National Standards Institute (ANSI) 119.5 standard and certified by an accredited third-party inspector, and is licensed and registered with the California Department of Motor Vehicles. It may not move under its own power, must have at least 100 square feet of enclosed space, and may be no larger than state law allows for movement on public highways. It must connect directly to an approved water source, an onsite wastewater treatment system or sanitary sewer, and electric utilities. Design standards require that the undercarriage (wheels, axles, tongue and hitch) be hidden from view, prohibit corrugated aluminum or fiberglass siding and shipping/cargo containers, and require residential-style cladding and at least double-pane windows with exterior trim.