What is an Accessory Dwelling Unit?

An apartment or a house that occupies the same lot with a larger house is called an Accessory Dwelling Unit (ADU). ADU is a legal term in real estate that describes a secondary house that shares the same building lot with a larger house, usually called the primary house. An independent but smaller residential apartment that is built in the same lot as a larger house or family house is an accessory dwelling unit. It can also be called some other names such as granny flats, secondary suites, among others.

How Does an Accessory Dwelling Unit Work?

When a stand-alone or detached building is constructed on a lot and another secondary apartment is built in that same lot, the secondary apartment is the ADU. ADU is otherwise referred to as carriage house, grant flat, in-law unit and secondary dwelling unit. An accessory dwelling unit is often attached to the main (primary) apartment, but it can also be constructed as a stand-alone. This apartment has all necessary rooms such as kitchen, living room and bedroom. It has had its entrance separate from that of the primary apartment. In the United States, zoning laws exist and serve as regulations on how ADUs should be constructed, stating their size and style. People build accessory dwelling units for different reasons. While some build it as a source of income, some build it to cater for family members. For whichever reason an ADU is constructed, it has pros and cons. They include the following;

• Accessory dwelling units are regulated by zoning laws. There is a limit to their style and size.
• These apartments attract upfront costs, housing costs and maintenance costs.
• Some ADUs are liable to taxation, especially those serving as a means of rental income. Constructing ADU can also cause a huge tax bill.

While some ADUs are legal, some are illegal, illegal ADUs can cause problems for the owner and even the investor. Building an ADU without permission from the zonal agency can attract certain penalties.

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