A housing unit, or dwelling unit, (at later mention often abbreviated to unit) is a structure or the part of a structure or the space that is used as a home, residence, or sleeping place by one person or more people who maintain a common household. A housing unit, or dwelling unit, (at later mention often abbreviated to unit) is a structure or the part of a structure or the space that is used as a home, residence, or sleeping place by one person or more people who maintain a common household.