Sarah Yeon is attached to her family’s Fairfax, Virginia, home. She and her husband, Abraham, bought it when they moved from South Korea in 2009 and raised their three children here. But more recently, after being locked down in the ranch-style residence during the pandemic with the kids, two of them now in their 20s and one heading into high school, she realized that they all needed more space. Buying a bigger house had crossed her mind, “but I loved my neighborhood and neighbors; I wanted to stay,” she remembers.

Renovating felt like “too much of a hassle,” says Sarah, but their backyard had plenty of space for a detached unit, especially since they could get rid of the kids’ dilapidated playground, which hadn’t seen use in years. Around the same time, Abraham, a chiropractor, happened to have a new patient who was getting their design business off the ground. Suddenly, the patient, David Lee, and his business partner, Sungjin Kim, had their first customers for their design firm, Aroom.

Sarah says working with the duo, who speak her native Korean, was a “gift from God.” Lee, the firm’s CEO, and Kim, who leads design and construction, collaborated with the Yeons on their ADU to create a space that the whole family could use, whether for studying, hanging with friends, or hosting guests.

Early sketches became more fleshed out, and ultimately emphasized affordability. “When we started the design, we were thinking of adding all these curves. We were focusing on the beauty aspect of it, but naturally, that becomes more expensive,” says Lee. They eventually landed on a rectangular, 216-square-foot plan made with panelized walls and topped with a modified gable roof. The Yeons requested storage space, so Aroom created a platform with drawers that serves as a reading nook or sleeping area large enough for a full-size mattress.

Material Costs + Contractor Fees

$280 Permit	$3,500 Site Upgrades & Landscaping	$1,500 Foundations
$5,500 Framing	$5,000 Metal Roof & Wall	$2,690 Waterproofing & Sheathing
$3,050 Rigid & Cavity Insulation	$3,500 Windows & Doors	$1,620 Interior Finishes
$1,170 HVAC	$2,000 Electrical	$1,000 Built-In Cabinetry
$500 Furniture	$1,000 Decking	$1,150 Additional Expenses
$12,204 Contractor Fees
Grand Total: $45,664

Itemized Contractor Fees

$1,050 Site Upgrades & Landscaping	$450 Foundations	$1,650 Framing
$1,500 Metal Roof & Wall	$807 Waterproofing & Sheathing	$915 Rigid & Cavity Insulation
$1,050 Windows & Doors	$486 Interior Finishes	$351 HVAC
$3,000 Electrical	$300 Built-In Cabinetry	$300 Decking
$345 Additional Expenses	$12,204 Total

The company has since honed its mission, which Lee says is “affordable but beautiful detached solutions.” To keep costs down, Lee and Kim designed the ADU as a “construction-ready set,” which provides a builder with a materials list, takeoff, project checklist, and plans that are “almost Ikea versions of drawings that are easy for contractors to follow,” says Lee.

The Yeons opted for Aroom’s turnkey offering, spending $45,664 to have the firm oversee the project from start to finish, with installation taking around 24 days. The unit includes some prefabricated parts, but its plans, now available for others to purchase, can be adjusted depending on a builder’s preferences. Lee says folks who are savvy and want to save a little more cash can buy the sets for closer to $1,000 and go DIY.

Developing the design system alongside the Yeons turned out to be a blessing for Aroom, since Lee and Kim established the company to serve suburban homeowners like them: families who need a little more space, but don’t have a renovation-sized budget. “Ease of construction and sustainability are key for us, which naturally reduces material cost and waste,” says Lee. “In the end, the Yeons’ support nurtured our mission of creating designs that are both beautiful and accessible.”

Sarah says that her family is thrilled with how the detached studio turned out, especially because it fosters community with neighbors and members of her church. She also views the space as a nod to the Korean 사랑방, or sarang bang, which was a dedicated room in a traditional hanok used for quiet activities. “A lot of Koreans used to name their sarang bang in honor of their family traditions. For us, we wanted to dedicate this space to our younger family members, so we call it 헌희당, or hunhee dang, which means ‘offering joy,’ because our kids love inviting people over,” says Sarah.

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