An accessory dwelling unit (ADU) is an independently habitable dwelling that provides shelter, heating, cooking facilities, and sanitation facilities for no more than one family. An ADU is accessory to, and on the same lot as, a primary single-family dwelling, duplex, commonwall dwelling, or multi-family dwelling on the same lot. It may be within or attached to the primary dwelling, or it may be a detached building on the same lot as the primary dwelling. An ADU is distinguishable from a duplex in that, unlike a duplex, it is clearly subordinate to a primary dwelling unit, both in use, size, and appearance.
