Mother-daughter apartments are considered accessory dwellings, according to the New Jersey Department of Human Services, and zoning that permits accessory dwellings varies by municipality. A list of municipal codes in New Jersey is available at GeneralCode.com.
Mother-daughter apartments are not two-family homes, but separate living spaces created from one single family home, according to Newsday. For example, one floor of an existing building may be remodeled with its own kitchen and bath to create an apartment.
Municipalities regulate accessory dwellings in order to maintain the character of the neighborhood and to ensure that homes meet health and safety standards, according to the New Jersey Department of Human Services. Often, the factors in zoning decisions involve minimum designated floor areas for the apartment and compliance with off-street parking rules. Property owners may apply for a variance if the property is not zoned for accessory dwellings.
It is easiest to create a mother-daughter apartment in an area that is already zoned for two-family homes because more design options are available, according to NorthJersey.com. A mother-daughter apartment is not required to have a separate entrance, as a two family home must. However, owners who make provisions to install separate entrances and utilities may be in a better position to rent the unit separately in the future if desired.