Hawthorne, CA Accessory Structures: Shed Rules (2026)

Under HMC Section 17.20.160, an 'accessory building or structure' is a detached structure incidental and subordinate to the primary building, expressly including sheds, detached garages, playhouses, storage buildings, garden structures, pool houses, and cabanas. Storage rooms and tool sheds 'for customary household related items shall be limited to a maximum of one hundred twenty square feet,' and while they 'may be wired for electrical service,' they 'shall not have any plumbing.' The code states there is no minimum required distance between accessory buildings and structures other than those specified in Section 17.20.060, but 'all buildings, structures, or fences shall maintain a distance of not less than ten feet from the center line of an alley.' Larger or habitable accessory buildings move out of the simple tool-shed category and are reviewed under the broader residential development standards in Chapter 17.20, and any accessory structure used for living space is regulated as an ADU under Chapter 17.21 instead. A building permit from Hawthorne Building & Safety is required once a shed exceeds the state exemption threshold (typically 120 square feet under the California Building Code).