"Flexible, manageable, romantic,” said Maren Reese, describing her accessory dwelling unit.

The 43-year-old, Philadelphia-based wardrobe supervisor for film and TV takes delight in extolling the virtues of her short-term Wilmington rental in the form of a fully renovated carriage house in the Carolina Place neighborhood.

Across the bridge in Belville in Brunswick County, homeowner and mortgage professional Kim Ackerson also has good things to say about her accessory dwelling unit, also known as an ADU: “They love it.” By “they,” Ackerson means her aging parents, who have moved into the 775-square-foot structure and living space attached to the garage of her family’s single-family home.

Defined as a separate residential living space on the same lot as a primary dwelling, ADUs are seeing a resurgence in the Port City and beyond, partly because of more relaxed zoning regulations and ordinances. ADUs, which must have a full kitchen and bathroom, can take many forms, from backyard cottages and carriage houses to above-garage apartments and tiny houses.

Historically, regulations and ordinances for such structures were stiffer, including location and size.

“Zoning ordinances have gone back and forth on the size of ADUs and the various restrictions placed on them,” said Kathryn Thurston, city of Wilmington zoning administrator. “But those restrictions have recently loosened, making it easier for residents to build these units.”

For example, ADUs are now allowed on nonconforming lots, or lots that do not meet the minimum area and/or width requirements under their zoning classification. Another change is size – ADUs can now be up to 1,200 square feet, whereas before, the limit was 900 square feet.

Still, some firm ground rules remain in the upward world of backyard building: ADUs can’t exceed 50% of the size of the primary dwelling and can’t be taller than it. ADUs must be set back at least 5 feet from side and rear lot lines.

Thurston said that almost all of the city’s 30,000 residential lots could be potential sites for ADUs. At present, there are approximately 700 ADUs citywide.

“We purchased our house in Carolina Place with an existing ADU in the form of a carriage house,” said Nory Simoneaux, whose tenant is Maren Reese. “It was not our original intention to rent it out. With space issues in the main house, we thought the additional space would be great for family.”

However, after a major renovation, including new siding and an updated kitchen and bathroom in the 450-square-foot upstairs apartment (think clean lines, pale, blue-coated walls and shiny hardwood floors), Simoneaux was ready to rent.
“We rent it out 50% of the time,” she said, “and we rent primarily to travel nurses. Usually three-month stints.”

For most property owners, the advantages of ADUs include increased property values, additional income, versatility and flexibility in use and a place for aging parents or visiting guests. Potential pitfalls include upfront construction costs, unit management and maintenance, added demands on water and sewer infrastructure and even disenchanted neighbors with noise and privacy concerns.

“We have (the carriage house) set up, so it has its own entrance,” Simoneaux said. “Renters park in the alley, so we have our separate comings and goings.”

For renters like Reese, renting an ADU over a traditional apartment comes down to flexibility, manageability and the option of a short-term rental, she said. “And I just love a carriage house and the energy of it.”

Simoneaux said rules regarding ADUs have come a long way.

“Zoning codes for ADUs were stricter years ago,” she said. “Many people shied away from building. Once the codes became more lenient, many people jumped on the opportunity.”

“It’s truly just a small house,” said Liz McKinley, referring, in this case, to the nature of a detached ADU.

McKinley and her husband, Sebastian Behmer, owners of local construction company BehmerHaus Inc., have experience in the local ADU environment.

In suburban areas like Pine Valley and Leland, said McKinley, more people are building ADUs for in-laws and aging parents. In Wilmington’s downtown, however, ADUs similar to Simoneaux’s carriage house – which BehmerHaus renovated – are being built or renovated with renters in mind.

No matter where and what for, the construction cost seems the same. For custom-built detached units, for example, the cost per square foot can average between $200 and $300. That means a 600-square-foot unit can cost between $120,000 and $180,000.

“It’s like building a house – foundation, framing, insulation, plumbing and roofing,” said McKinley, who happened to build an ADU for her aging father. “It allows him a nice, independent life.”

But not all ADUs need cost that much, McKinley said. “It just depends on what you want and how extensive your plans are.” McKinley mentioned “time, design and money” as the main determining factors.

As far as design, McKinley said some homeowners employ architects or designers, and some just choose a plan online. Ackerson did the latter.

“I searched online for building plans with ADUs,” said the Swansboro native, “then found one that had potential and then had that company modify it to our specifications.”

Ackerson, who also used BehmerHaus, said construction of her ADU – which, due to HOA restrictions, needed to be attached to the garage – was easy.

“We didn’t have any issues,” she said.

The result?

“A full kitchen, full bath, bedroom, small crafting room for my mom, laundry room and living area,” Ackerson said.

Ackerson said construction costs were about $60,000, and she intends to rent it out at some point.

McKinley warned that HOAs, or homeowners associations, may have different rules and regulations for ADUs. “Be sure to call your HOA and check on the various zoning regulations before spending money on things like getting your lot surveyed,” she said.

For those without an HOA, McKinley offered similar advice. “Engage zoning early on and ask questions. Troubleshoot early on.”

That’s something Thurston, as Wilmington’s city zoning administrator, echoed.

“Educating people with tools on housing and ADUs is always helpful,” she said, adding that the city is always looking for ways to improve the various zoning ordinances conducive to more ADUs. “We want feedback on any impediments to the process.”

Outside city limits in the county, ADUs are a fairly recent, if not somewhat scant, phenomenon.

“ADUs have only been allowed in the county and unincorporated areas since 2023,” said Rebekah Roth, New Hanover County planning and land use director. “Some are newly constructed, while others are existing units brought into compliance.”

Roth said around five ADUs now exist in the county, since the ordinance passed. Interest in ADUs is on the uptick, however, she said. Still, challenges remain.

“For subdivisions with HOAs, ADUs might not be permitted. Then there may be certain impervious surface considerations. Then sewer and septic tank capacity concerns,” she said.

As far as permitting, Roth said ADUs in the county are “constructed to the single-family dwelling building code.”
Roth said the backing behind the ADU ordinance boiled down, in part, to economics.

“Smaller units are often more affordable (for renters), and the property owner is able to generate income,” she said.
Indeed, some municipal officials opine ADUs may partly solve the region’s affordable housing crisis.

But that seems a big ask, especially to seasoned public officials like Thurston.

“The solution to affordable housing is going to have to be more than just ADUs,” she said.

Until then, it’s likely more ADUs will continue to drop anchor in the Port City.

“People definitely want them,” Simoneaux said. “If you look at a house with an ADU, it’s a definite commodity. If you can’t get it, build it.”