Are ADUs the perfect housing solution?

Author Sheri Koones titled her newest book ADU: The Perfect Housing Solution, so she thinks they are. Here she talks about researching accessory dwelling units for her book, their origins, what makes them special, and her reasons for calling them “perfect.” This interview has been condensed and edited for clarity. You can find more about the ADU projects Koones showcases in the article "ADUs May Have Cute Names, But They’re Serious Business."

Jay Schneider: Your book features 25 ADUs. What stood out about these projects?

Sheri Koones: I looked at over 200 ADUs before I chose them. I'm very fussy about what I include in my books. They have to meet the standards of what I'm writing about, and they have to be very attractive on the outside as well as on the inside. I wanted a good variety so people understand what’s possible. I wanted ADUs from different parts of the country and I wanted different sizes and types—some are above a garage, some are separate, and some are attached. Some are prefabricated, some are built on site, and mostly all of them are very energy efficient.

JS: I was surprised to read that ADUs are relatively new to the U.S., having origins in Canada after WWII.

SK: Canada used them because there was a shortage of housing after the war. They converted the separate garages that opened to a laneway or alleyway, and it worked out really well. They became popular in the U.S. really about 20 years ago when people on the West Coast thought that would work well for them. And now they’re becoming more popular around the country.

JS: You refer to ADUs as the perfect housing solution. What do you think makes them so perfect?  

SK: One of the biggest problems we have in this country is a shortage of housing, and an ADU is a great solution. You can put one behind your house so you don't even see it, and they afford people extra income and provide extra housing. I don't really see any negatives to building them. It's really a win-win for the homeowner and for people living in the ADU. They really are a perfect little place that has everything.

JS: Did anything surprise you when researching ADUs?

SK: I’ve always been fascinated by the whole concept of ADUs, and I guess I’m always surprised by how beautiful they can be and how people can use a small space and make it so livable. The whole idea is using your space in a worthwhile way. A lot of homeowners I’ve spoken to have also built ADUs with the idea that they will live there at some point. If I was buying a house today, I would only buy one where there was room for an ADU.

JS: When you were selecting ADUs for this book, did you find ones that didn't work or had weak spots? And if so, what did you find?

SK: I found a lot of ADUs that looked very nice on the outside, but the interiors weren’t as nice. It’s very important that they be well designed inside and out. They’re small spaces but they need to feel larger than they actually are, so that means high ceilings, light colors, and lots of windows for natural light. Also, it’s important where they’re positioned on a property so that there's privacy for the people living in both the main house and the ADU.

JS: There are prefab and site-build ADUs. Have you found one type to be better than the other?

SK: I think it depends on where you live. In some areas, labor is so inexpensive that it pays to build it on site. But if you're not in one of those areas, you should definitely consider prefab. And prefab can be faster and it’s a much more efficient method. The house on the cover of the book is prefab and it really is beautiful.