What Is An ADU? Will It Add Value to Your Home?

ADU’s, or accessory dwelling units, have been all the “rage” in recent years as everyone seems to be talking about them from coast to coast but the big question is what exactly are, they and how can you get one if you’re a homeowner in the ATX area?

Accessory Dwelling Units Defined

ADU stands for Accessory Dwelling Unit and they might just be your next edited home. You might know ADUs by their other, quasi-affectionate names such as granny-flats, mother-in-law-apartments and so on. They are dwellings–either attached or detached from the main house–that exist on a lot with another house. Many ADUs are built above garages such as the one pictured above.

ADUs have myriad benefits such as:

  • Creating a secondary rental income.
  • Increasing the occupancy of a given plot of land.
  • Creating more communal living, while still providing autonomy and privacy for both homes.
  • People who may have once needed a large home–e.g. parents whose children have moved out–can move into the ADU and rent out the main home.

ADUs are not lean-to’s; they are real homes that require building permits and some investment. A great resource is, which goes into the ins-and-outs of ADU construction, financing, zoning for every state and other issue.


What Are the Regulations for Building an ADU in Austin?

Although you may be a homeowner in the ATX area, there are a variety of regulations that you must follow if you want to build an ADU on your property.

  • Your lot must be at least 5,750 square feet to build an accessory dwelling unit.
  • Your accessory dwelling unit can be a maximum size of 1100 square feet or 15% of the lot size, whichever is smaller. For example, if you’re lot size is 8,000 square feet than 15% of your lot size is 1,200 square feet. 1,200 is larger than the maximum, 1,100 allowed, so the max you can build is 1,100 square feet.
  • Building cover for the site may not exceed 40%. Essentially meaning the city doesn’t want houses filling up more than 40% of the lot if you’re looking down from an aerial view.
  • Your main house and the accessory dwelling unit must be separated by 10 feet front to back and side to side.
  • You must provide one parking space for your accessory dwelling unit in addition to the primary structure of parking you already have on your property. If you live within a ¼ mile of a transit stop, you do not need to provide additional parking.


Learn More

To learn more about building an ADU in the Austin area, or to speak with us about buying a home in Austin, contact us today by calling (512) 944-7378 or click here to connect with us online.