What is the definition of an Accessory Dwelling Unit (ADU)?

  • An ADU is an architectural term for Accessory Dwelling Unit. An Accessory Dwelling unit generally must have a electricity and plumbing, a sleeping area, cooking facilities and a bathing area.
  • An ADU may be a free standing separate structure with external access separate from the main house
  • An ADU might be a garage conversion if allowed by local ordinance.
  • An ADU might be a divided part of an existing house that has an outside entrance.
  • An ADU might be an apartment over a garage or and apartment made from a basement.
  • All ADU’s must meet the local building code and standards for health and safety.

What are other names for an ADU:

  • Some locations use Casita in lieu of ADU
  • Other names might be Carriage House (typically above a garage)
  • Mother-in-law apartment

Why are ADU’s such a current hot topic?

  • Due to a housing shortage across the nation, many municipalities, counties and states are encouraging ADU’s to be built new, a removal of penalties for declaring an existing rental unit to be an ADU.
  • Some states and locals, are allowing a homeowner by right to build an ADU on their property. (this has not always been the practice)
  • Apartments are sometimes hard to get built due to cost, zoning or location.

What is the advantage to having an ADU?

  • Extra income as a rental for a college student, a senior or a caregiver
  • An ADU can bring an elderly parent to live close but independently.
  • Or a new graduate from school that needs a place to live that is more affordable than an apartment.
  • An increase in the property value
  • A good return on the investment if built, rented and eventually sold with the house.

Are the disadvantages to having or building an ADU?

  • There is an initial cost of the architectural design work.
  • The permit process, though this is generally streamlined to encourage this type of development.
  • The cost of construction. Like many things recently, the cost of lumber, fixtures, wiring and related materials has risen.  An ADU may cost $50,000 to over $100,000, depending on size, location and amenities.
  • Lately, finding a contractor and skilled labor to build has been an issue, though this may fluctuate depending on the local market.
  • Lastly, some neighbors may object to having more people in the neighborhood. This can be a more local individualized issue, but can be an objection to some.  Check with your local building department as to your right to build an ADU.