In unincorporated Alameda County, storage sheds under 120 square feet without electrical or plumbing are exempt from building permits. Larger sheds require permits. All sheds must meet setback requirements and height limitations.
Under the California Building Code as adopted by Alameda County, detached accessory structures used for storage (sheds) under 120 square feet that do not have electrical or plumbing installed are exempt from building permits. However, these exempt sheds must still comply with zoning requirements: they must be placed in the rear yard, maintain a minimum setback of 5 feet from the property line if the structure exceeds 9 feet in height, and must be no more than one story and no higher than 15 feet. Sheds must also be at least 6 feet from the main dwelling or any other building. Sheds over 120 square feet require a building permit, and any shed with electrical, plumbing, or mechanical systems also requires permits regardless of size. Starting January 1, 2026, all building permits must comply with the 2025 California Building Codes. Permit applications for unincorporated Alameda County are submitted through the Alameda County Permit Portal.
Unpermitted sheds over 120 sq ft or those with unpermitted utilities are building code violations. The county may require retroactive permits, modifications, or removal of non-compliant structures. Setback violations may trigger zoning enforcement actions.
Other ordinances people look up for this city. Green dot = verified primary-source excerpt.
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