Accessory Dwelling Units (ADU's)

An ADU is a self-contained unit that is part of or built alongside an existing home. Having one of these units as part of your property can make it easy to resell, as they are very popular with buyers. So when you are looking at buying a new home, choosing one that already has a guest unit on one side or an over-the-garage apartment attached can be a very good choice. Even a small cottage alongside the main house on a large lot can be considered as an ADU for zoning purposes.

Why Have An ADU

Having a small separate self-contained apartment alongside the main house gives you a lot of flexibility. You can use it for a home office, somewhere for your college kids to live in during vacation, as a guest apartment for friends and family, or even to enable elderly relatives to live close by, but with their own privacy.

Renting It Out

Many people who have ADU's rent them out for additional income. If you live in a college town for example, you can rent out the ADU to staff or students. This can give you a reasonable income and help you to pay off your mortgage quicker. Another option, especially if you are downsizing, is to move into the ADU yourself, and rent out the main part of the house. This gives you greater income and may even be enough to pay the whole mortgage. If you are planning to retire in the area, you can use the ADU apartment as a base for weekends or vacations, while you get to know the neighborhood. Meanwhile someone else is living in the main house, paying your mortgage, and keeping an eye on your property.

Shell ADU's

When you are looking for a house with an ADU attached, you may find that the builder has provided a shell above the garage, to the side of the house or given you an unfinished basement. This gives you the potential to upgrade the shell to an apartment at your leisure. Then when you need a guest apartment or additional income, you can apply for any necessary building permits, get construction quotes and then finish your shell, giving you your extra living space.


Many towns and cities now allow ADU's in single-family neighborhoods as it helps to increase the availability of lower priced accommodation without changing the basic nature of the neighborhood. Zoning laws vary from place to place so you need to check to see if there are any restrictions on who may live in your ADU. ADU's also help to maximize use of public services and increase the municipal income from taxes. Enabling people to move into and continue to stay in an area because of the increase of accommodation available helps to keep neighborhoods vibrant. ADU's can also help to preserve historical buildings and are a sustainable way of increasing housing stock without negatively affecting the overall environment. In some areas, developers of new-build even incorporate an ADU as part of the overall design.

By choosing to buy a property with an ADU you are giving yourself a lot of flexibility as your circumstances change throughout your life. You may even find you never have to move as your family grows and shrinks. And of course, if you choose to sell, you will find it easy to find a buyer.