Cal. WIC § 5116

(a) Pursuant to the policy stated in Section 5115, a state-authorized, certified, or licensed family care home, foster home, or group home serving six or fewer persons with mental health disorders or other disabilities or dependent and neglected children, shall be considered a residential use of property for the purposes of zoning if the homes provide care on a 24-hour-a-day basis. (b) These homes shall be a permitted use in all residential zones, including, but not limited to, residential zones for single-family dwellings.