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Home Visit: Detached Bedroom ADU

St. Petersburg, Florida | 240 square feet

Detached bedroom ADU

Photo by Historic Sheds

A detached bedroom, such as this one in St. Petersburg, Florida, contains a bathroom but no kitchen. It can provide housing for a loved one or serve as a home office or guest cottage.

Bertha and her son John talked about someday buying a house with a mother-in-law suite. “Then one day someone came along and wanted my house, so I up and sold it,” she explains. “But that left me homeless. I asked John if I could build a small house in his backyard and he agreed.”

CREATIVE THINKING: A detached bedroom is a permanent, accessory structure that, unlike ADUs, lacks a kitchen. But that’s what makes these cabin-like homes more affordable to build than many ADUs and even tiny houses.

WHAT’S INSIDE: Bertha’s home contains a sleeping and living area and a full bathroom. “I paid for the little house and it’s on my son’s property. So I figured, if I’m cooking I can do it at my son’s house,” she says. (Her laundry is also done at his house.)

REAL LIFE: “Having access to my son’s house makes it livable. Otherwise, I personally would not be happy. It’s very comforting to know that John is close by. Hopefully this will be my home forever.”

Design: Historic Sheds
Builder: Historic Sheds
Cost to Build: $50,000 in 2017

While not technically ADUs, tiny houses can serve similar purposes

Backyard tiny house

Photos by Guillaume Ditilh, PhotoXplorer

Because tiny houses — such as the 100-square-foot- "Lucky Penny," pictured — are build on a trailer with wheels rather than on a fixed foundation, they are typically classified as recreational vehicles (RVs) rather than permanent residences. Although tiny homes are usually smaller than 400 square feet, many of them do contain a kitchen and bathroom.

Designer and Builder: Lina Menard, Niche Consulting

Article adapted from “ADU Case Studies” by Lina Menard on and The ABCs of ADUs by AARP.


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