Accessory dwelling units (ADUs) are backyard cottages up to 1,200 square feet.
An ADU is a small permanent home that may be established in addition to the main dwelling on a parcel zoned for residential use. ADUs may be attached or detached from the main dwelling.
Most residential zoning districts allow one ADU unless there is a "Z" (Accessory Dwelling Unit Exclusion) overlay zoning on the property..
ADUs can be rented for long-term occupancy, but they cannot be used as vacation rentals.
Read More about Accessory Dwelling Units