Grass Valley, CA Accessory Structures: Shed Rules (2026)

Nevada County follows California Building Code permit exemptions for small accessory structures. Per County guidance on work exempt from permits, one-story detached accessory structures are permitted without a building permit where the floor area does not exceed 120 sq ft, and these are not limited in number. A larger exemption applies to one-story detached accessory structures up to 200 sq ft, provided the structure has no electrical, mechanical or plumbing systems, is not intended for habitation, has a maximum 2-foot eave, and is limited to one such structure per parcel. Once utilities (electrical, plumbing, or mechanical) are added, the permit exemption no longer applies and a building permit is required. Even when a shed is exempt from a building permit, it must still comply with the applicable zoning district setbacks from property lines and other site development standards in the County's zoning regulations (now Title 12 of the Nevada County Code). Larger detached structures, or any structure intended for habitation, require a building permit and must satisfy zoning standards for accessory structures, including height limits and setbacks tied to the parcel's zoning district. Property owners are advised to confirm setbacks and septic/well clearances with the Community Development Agency before building.