Accessory Dwelling Units: What Exactly Are They?
Mother-in-law cabins, secondary suites, cottages, and self-contained apartments are synonyms for an accessory dwelling unit (ADU). It's an old and simple idea to have a small, second home attached to or on the same property as your primary residence such as:
- a small house on a foundation in the back or side yard
- an apartment over or attached to the garage
- a basement apartment
The demand for ADUs is steadily increasing and many are wanting to understand these units and their benefits further. In this article, we discuss:
Types of Accessory Dwelling Units
- An ADU above a workshop, above a garage, or attached to a garage—known as carriage houses and garage apartments.
- A detached ADU new construction—known as granny flats, mother-in-law cabins, backyard cottages, or laneway houses. It depends on the jurisdiction.
- Garage conversation ADUs
- Bump-out ADUs also known as Addition ADUs
- Basement conversion ADUs
- Internal ADUs - a part of the home besides the basement is converted.
Related: How to Build the Perfect In-Law Unit
Commonalities of Accessory Dwelling Units
There are various structural forms of accessory dwelling units. However, there are a handful of traits, design aspects, and development obstacles that ADUs share. Their first commonality is that they're in a unique housing category. Take a look at a few other commonalities of ADUs:
It is all of these distinctive characteristics and more that make ADUs a unique type of housing. With a more cohesive language and understanding of accessory dwelling units, there's now a deeper understanding of the best practices in ADU development than ever before.
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Increased Demand for ADUs
In the recent past, cities have been more eager than ever to improve the ADU codes in their area. It begs the question: why all this sudden demand?
The average size of a household in America used to be 4 or 5 people. These days, the average is 1-2. Despite this considerable difference, most of our past and present housing is designed for families of 4-5. That may have made sense 80 years ago, but not today because households with 3-4 bedrooms are a poor match for the American demographic for two reasons:
- Our average household size is no longer that large.
- The average household income is nowhere near enough to support such a large home, as it's not just houses that are more expensive but also the upkeep for it.
The statistics are quite staggering. Only 38% have 3+ people living in them. The other 62% are 1-2 person households. That means that 1-2 person households make up 2/3rds of the US population!
Those who live in smaller households have had trouble securing housing that's an appropriate size. Often these folks have to rent or buy a larger home than they need because it's simply all that's available on the housing market.
For these reasons, the demand for accessory dwelling units is only expected to rise.
Related: 10 Best Backyard Workspaces
City Interest in ADUs
Cities have a variety of reasons why it is in their best interest to encourage ADU development.
Environmental - The environmental footprint of ADUs is barely noticeable compared to larger family homes. A new ADU that's detached is about 44% smaller than a standard home. Overall, new ADUs are about 33% lower than the standard. Smaller homes, apartments, and living spaces use far less energy regarding habitation, construction, and deconstruction through the building lifecycle.
Economic - Accessory dwelling units can offer more affordable and flexible real estate options in metropolitan cities. Usually, the dwelling units utilize governmental infrastructure that already exists like schools, sewers, and roads. For this reason, accessory dwelling units reduce the need for expansion in already overcrowded central cities.
Social - ADUs benefit the neighborhoods they're in because they can offer growth without much physical expansion or change in the neighborhood character.
ADU Tips for Looking Good
ADUs are incredibly beneficial to those who they're appropriate for. These units can be great fun to aesthetically design and decorate--and, it's much more economical. Because a renter or an owner has less to buy, they can usually spend nicely on what they do choose to have in the home. This extra bit of economic and decorative flexibility leaves some ADUs looking far nicer than regular homes!
Here are a few tricks to make the most out of your accessory dwelling unit:
- Coordinate the outside of the ADU with the main home's exterior.
- Place your windows as high as possible to let the max amount of light enter.
- Contemplate vaulted ceilings. They create more room.
- Cultivate open spaces--don't waste any square feet!
Frequently Asked Questions
Yes. A permit is required from your local jurisdiction to permit you to build. In some areas, the exception to the rule is if the space is under 200 sq ft and uninhabitable, but in all other cases, a building permit is required.
As always, check with your specific jurisdiction to get informed of the regulations in your area.
Yes, the kitchen is what makes it an accessory dwelling unit. The kitchen is what sets it apart from other living spaces. They are a requirement in ADUs.
That depends entirely on your local laws and regulations.
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Related: How to Get a Permit for an In-Law Unit
Final Thoughts
This form of housing has limitless potential, and we will see more of it in the future. They can provide rental income for many, offer affordable accommodations for others, and offer families a way to stay together while maintaining a comfortable distance.
Are you looking for residential and commercial site plans for permits? Contact My Site Plan today!
- Annie Rosellini
