Accessory Dwelling Units: The Granny Flat Update

This week’s blog begins a series on a particularly varied form of aging-in-place — accessory dwelling units (ADUs). While the term may sound like something the Conehead family from Saturday Night Live’s early days invented, ADUs are remarkably flexible living spaces that can be perfect for both creating additional income and staying in a beloved community. In addition to serving as either income property or family housing, ADUs also can be used as quiet workshops or office spaces.

What is An ADU Anyway?

An ADU is a small, independent, residential dwelling located on the same lot as another existing residence — usually a single family home. ADUs go by a variety of nicknames — granny flats, in-law suites, carriage houses, backyard cottages, and the like — and can be attached or detached to the primary structure as:

  • External new construction, such as tiny houses
  • Garage or workshop conversions
  • Additions, such as those built onto the side of the single family home
  • Basement conversions
  • Internal ADUs, where part of the single family home (not counting the basement) is converted to an ADU, e.g., an entire third floor.

ADUs must provide for living, sleeping, cooking, and bathroom facilities and be on the same property lot as the primary dwelling.

Isn’t This Another ‘Old/New’ Idea?

ADUs are a new trend based on an ancient idea: people finding ways to stay in their communities as they age. Many families can remember a time when grandparents and other adult family members shared housing for economic reasons. The tradition of multiple generations living together and supporting each other can be traced to the dawn of many cultures in today’s world.

The COVID-19 pandemic also reawakened people to their ability to thrive in smaller spaces and, as restrictions were lifted, a greater appreciation of their community and family members.

So Why Build An ADU?

There are a number of practical reasons to build an ADU. If built to rent out, the rent collected from an ADU can allow homeowners to stay in their home as they age. An ADU can make an ideal Airbnb rental space.

Additionally, an ADU can add value to a property. It’s always a good idea to discuss a possible ADU project with a financial advisor. ADUs may increase property taxes and — like the primary residence —will require maintenance. Careful planning ahead of time is a necessity.

ADUs also can increase flexibility and possibilities — the double win for Baby Boomers. Some ADU owners rent out their primary homes and use their ADU as a home base for travel. Others begin by renting out their ADU. As age and medical problems arise, they “swap” — moving into their ADU and renting out their primary home in order to stay in their community. Let the creative ideas blossom!

ADUs also provide a convenient space for a family member to live in — either a younger family member who can provide support and care to an older member, or an older family member who wants to live with family as close as across the lawn.

Are ADUs Allowed Where I Live?

Not all communities allow all types of ADUs to be built. There are permits and requirements that vary by locality, so at the start of the planning process, it’s time-saving to check with local ADU builders and learn the requirements of the given municipality.

However, many communities are fast-tracking changes in housing development regulations to meet demand for ADUs. Cities are realizing that there are many potential economic, environmental and social benefits connected with the increased development of ADUs. Next week, I will delve into some of these community-wide benefits, as well as address more individual benefits of ADUs. As with everything, the key to creating a successful ADU is careful, proactive planning, and the benefit is the increased flexibility that allows a fruitful, creative, and fully realized Third Chapter Life.

Third Chapter Living celebrates, challenges, informs and promotes conversations about housing issues affecting the Baby Boomer Generation. Check out our website to learn more about our work. Our Facebook Group is a resource center with tips and recommendations on navigating those issues. Share experiences with others who are looking for Housing Downsizing Tools that allow them to successfully age in place.


  1. Fay Kennedy on August 29, 2022 at 12:12 pm

    Thank you for these great resources !

    Special thanks goes to Reese Fayde who has provided his research and knowledge relevant to aging in place… all the info on downsizing and alternative living spaces i.e. (ADUs)……

    I am on the hunt for an ADU rental in Virginia Beach……
    Wish me luck…….

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