Idaho Falls, ID Accessory Structures: Shed Rules (2026)

Idaho Falls building rules require a building permit for any detached structure, including a shed, over 120 square feet that will house property, equipment, or people. Sheds 120 square feet or smaller are exempt from the building permit, but they must still comply with the zoning ordinance. Under Title 11, zoning provisions require front, rear, and side yards to be kept open and unobstructed, so even a permit-exempt shed must respect setbacks. In residential zones, the rear yard setback for accessory buildings is three feet (3') where a rear yard applies; where an alley runs at the rear of a lot, a three-foot rear yard is required. Side yard requirements for accessory buildings are the same as for main buildings, except that no side yard is required for an accessory building located more than twelve feet (12') behind the main building. No accessory building or group of accessory buildings in a residential zone may cover more than thirty percent (30%) of the rear yard. Because of eastern Idaho's snow and wind loads, the city's review confirms the structure can carry required loads in addition to verifying location, so larger sheds are inspected for both zoning and structural compliance.