An accessory dwelling unit (ADU) is a small, self-contained residential unit located on the same lot as a single-family home. The ADU may be a separate unit within a home (such as in an attic or basement), or be a detached structure (such as a converted garage, not attached to the primary home). The entry door to the ADU is separate from the main residence. The single-family home and ADU are owned by the same person and may not be sold separately. This brochure describes some of the key features of an ADU.