Townhouse Dwelling. A one-family dwelling in a row of at least three such units in which each unit has its own front and rear access to the outside, no unit is located over another unit and each is separated from any other unit by one or more common fire resistant walls.

Condominium Dwelling. A one-family dwelling in a structure of at least three such units in which each unit has direct access to the outside or to a common hall, units can be located atop one another, back-to-back units are prohibited and each unit is separated from any other unit by one or more common fire resistant walls.