Previously, you needed a 4,500 square foot lot, or larger, to build an Additional Dwelling Unit (ADU), also commonly known as a granny unit. Now, any legally built unit within the existing footprint of your home can be turned into an ADU under new state law.
This applies to new projects and conversions, so long as the unit is within the pre-existing structure and is build legally (meaning it was permitted and build to code).
Due to some confusion in the City Planning Department about the interpretation of state law, the City’s Law did not appear to conform to the new statewide regulations. Fortunately, according to this Sentinel Article, the city attorney confirmed that, under state law, property owners have the right to build an ADU within an existing structure regardless of the lot size.
Note: if you are building a brand new structure or making an addition to a pre-existing structure, you still need a minimum of 4,500 square feet. The state law only exempts ADU construction within an existing house or an existing accessory building.
To find out what it takes to build or convert an ADU in the City of Santa Cruz, visit the Planning Department during normal business hours.