Chapter 01: What is an ADU (Accessory Dwelling Unit)?
ADU stands for accessory dwelling unit, but it can go by many other names, such as mother-in-law unit, granny flat, guest house, pool house, casita, etc. They are built attached to a main house, or they could be stand-alone units.
Sizes of ADUs can vary, but they are typically the size of a small apartment or cottage with their own entrance, kitchen, and sometimes even laundry facilities.
Many times the term ADU is used interchangeably with the term "tiny house". But tiny house really describes a smaller, more mobile cousin of the ADU. And while they both may fall in similar genres of architecture, it is important to note their key differences.
Typically, when referring to an ADU versus a tiny house, the main difference is that an ADU resides on a permanent foundation and is not designed to be mobile, whereas a tiny house is designed to be easily relocated. A tiny house may even be attached to wheels, or reside on a trailer.
The experience of living in an ADU is one of a higher level of permanency. Certainly it's size is much more accommodating to long term living. An ADU can be designed with fewer restrictions than a dwelling that must never be wider than a street lane.
And while tiny houses are certainly a fad to watch on HGTV, the more realistic route for many homeowners is to construct an ADU which compliments the existing home's architecture.
ADUs are rapidly gaining popularity here in California, where housing is in high demand and the supply of affordable housing is severely limited. This makes ADUs an incredible investment opportunity, which we will discuss in the next chapter.
The 2019 Guide to Building an ADU in California
(Including Financing Options)
For homeowners who want to make the smartest investment when building a backyard cottage, granny flat, accessory dwelling unit, or garage apartment.