So-called “Granny Flats” might just be the next big trend in real estate rentals. Formally called “Accessory Dwelling Units” (ADUs) and more informally known as “mother-in-law apartments”, these homes were given their nicknames on the basis of their small size, and for their placement on the grounds of an otherwise single-family home. They were initially meant for and primarily used by aging grandparents, parents, young adult members, nannies, caregivers, or others who need a self-contained living area big enough for one or two people.


There has been a popular surge of interest in tiny house living, especially with our current trend towards multigenerational housing and the financial barriers the housing crisis poses to more traditional accommodations. CityLab estimates that by 2020, ADUs will take off in popularity as more units enter the market and provide a ready accommodations alternative for those seeking affordable housing.




Some granny flats are miniatures of full-sized housing units and have complete kitchens, while others are limited to a small refrigerator and a microwave. If needed, high-tech monitoring allows remote access to check on the inhabitant and even a timed medication dispenser along with other devices that can monitor the health and well-being of the older person.


Because of the ADU’s limited size, it is recommended to have a “great room” that combines the dining room, the living room, and the kitchen. If the room has high ceilings and a visual connection to the outdoors, it will make the space appear bigger as living quarters that fit much better into the budget of the elderly who have limited income.


Research has shown that senior citizens do best when they have social contacts, so living close to younger family members makes that possible and enjoyable for grandparents, who may also offer some child care and transportation to relieve the parents.


Are There Barriers?


Check municipal statutes, building restrictions, zoning laws, neighborhood covenants, and other pertinent regulations. It may not be too difficult if you are converting a garage or other existing structure, but building a new structure can be overwhelming due to the expense and the above laws. A prefabricated or modular building may be the answer, but this type of structure is prohibited in some communities. Some homeowners have tried to use the ADUs as rental units, but deed restrictions and zoning laws usually ban renting.


In 2017, California adopted legislation that minimized the laws on providing separate parking spaces for ADUs on property and reduced other law provisions. For example, that allowed Los Angeles to go from issuing 142 ADU permits in 2016 to approximately 2,000 in 2017. Cities that have ADU-friendly legislation are seeing and uptick in demand for ADUs.