Pleasanton, CA Accessory Structures: Garage Conversions (2026)

Converting a garage into living space in Pleasanton is most commonly done as an ADU under PMC Section 18.106, which incorporates California's state ADU law (Gov. Code Section 66310 et seq.). A key state-mandated provision in the city's ADU handout: when an existing garage, carport, or covered parking structure is demolished in connection with building an ADU, or is converted into an ADU, those off-street parking spaces are not required to be replaced. This removes a major obstacle to converting a tuck-under or attached garage. The handout also notes that an ADU resulting from the conversion of an existing accessory structure may retain its existing height and setbacks; however, any new addition built onto that structure for the conversion must comply with current ADU standards (for example, 4-foot side and rear setbacks and the 16-foot height limit for detached units). Conversions of existing space may exceed the standard ADU size caps and are not required to provide additional ADU parking. A separate building permit is required for the conversion, submitted through the Building and Safety Division portal, and a deed restriction is recorded. Converting a garage to non-ADU habitable space (such as a den or extra bedroom) instead requires the home to still satisfy its underlying off-street parking requirement, so most homeowners pursue the ADU path for flexibility.