Shasta County, CA Accessory Structures: Garage Conversions (2026)

Garages in Shasta County are residential accessory buildings governed by Section 17.88.140 of the Shasta County Code, but converting a garage to habitable living space changes the use and triggers a Shasta County building permit administered through the Department of Resource Management's 'Build Shasta' online portal. Two common conversion paths exist. Conversion to an ADU is the most permissive: under California Government Code section 65852.2(a)(1)(D)(iii) and (vii), an ADU may be located within an attached garage or other accessory structure, and no setback can be required for an existing accessory structure that is converted to an ADU (or for a new structure built in the same location and to the same dimensions as the existing structure). Subsection (a)(1)(D)(xi) further provides that when a garage is demolished in conjunction with construction of an ADU or converted to an ADU, the county shall not require that the lost off-street parking spaces be replaced. Permit review is ministerial within 60 days. Conversion to non-ADU living area (bedroom, family room, etc.) requires a Shasta County building permit, must meet California Residential Code requirements for habitable rooms (light, ventilation, ceiling height, egress, smoke/CO alarms, fire separation), and the converted area then counts as part of the primary residence rather than as accessory floor area. ADU conversions must still comply with California Building and Fire Code for habitable structures, including sound walls and foundation, utilities (electricity, water, sewage), HVAC, and proper insulation.