For purposes of the Municipal Density and Missing Middle Housing Act:

(1) Accessory dwelling unit means an interior, attached, or detached residential structure that is used in connection with, or that is an accessory to, a single-family dwelling and is located on the same lot or parcel as such single-family dwelling;

(2) Affordable housing means residential dwelling units affordable to a household earning not more than eighty percent of the income limit as set forth by the United States Department of Housing and Urban Development under its Income Limits Documentation System, as such limits existed on January 1, 2022, for the county in which the units are located and for a particular household size;

(3) City means any city of the metropolitan class, city of the primary class, or city of the first class in the State of Nebraska with a population of at least twenty thousand inhabitants as determined by the most recent federal decennial census or the most recent revised certified count by the United States Bureau of the Census;

(4) Cottage cluster means a grouping of no fewer than four detached housing units per acre with a footprint of less than nine hundred square feet each and that includes a common courtyard;

(5) Density bonus means a density increase over the otherwise maximum allowable residential density under a city's zoning codes, ordinances, and regulations;

(6) Middle housing means:

(a) Duplexes;

(b) Triplexes;

(c) Quadplexes;

(d) Cottage clusters; or

(e) Townhouses;

(7) Townhouse means a dwelling unit constructed in a row of two or more attached units where each dwelling unit is located on an individual lot or parcel and shares at least one common wall with an adjacent unit; and

(8) Workforce housing means:

(a) Housing that meets the needs of working families;

(b) Owner-occupied housing units that have an after-construction appraised value of at least one hundred twenty-five thousand dollars but not more than two hundred seventy-five thousand dollars to construct;

(c) Owner-occupied housing units for which the cost to substantially rehabilitate exceeds fifty percent of a unit's assessed value;

(d) Upper-story housing for occupation by a homeowner; and

(e) Housing that does not receive federal or state low-income housing tax credits, community development block grants, HOME funds as defined in section 81-1228, or funds from the Affordable Housing Trust Fund.