Mike Greenhalgh, left, is part of a neighborhood group that opposes the new Common Living development on his quiet street of early 20th century rowhouses in Northwest Washington. (Michael S. Williamson/The Washington Post)

When Mike Greenhalgh and his wife bought a 12-foot-wide brick house on Richardson Place NW four years ago, the alley’s tranquility was a key attraction. “This was a little gem of a street in D.C.,” Greenhalgh, a semi-retired engineer, said as he sat in a cozy back room warmed by afternoon sunlight. “It’s a little street from nowhere to nowhere.”

But he and his neighbors worry that their bucolic enclave of early 20th-century rowhouses nestled between Shaw and LeDroit Park is about to be taken over by a 21st-century model of hipster living. A new development comprising three above-ground stories-plus-basements on what was once five empty lots is slated to become the first D.C. outpost of a company called Common Living, which will rent out 24 bedrooms on the premises.

The Richardson Place Neighborhood Association, which formed last fall in response to the project, has filed an appeal asking the city’s Board of Zoning Adjustment to rescind the development’s building permit. The association also plans to ask the Advisory Neighborhood Commission for support at a meeting Tuesday, in advance of a zoning board hearing March 22.

Common, which has similar properties in New York and San Francisco, advertises to young professionals. The two-year-old company offers furnished, private bedrooms, some with private bathrooms, and shared kitchens and lounges, along with weekly cleaning service, towels, laundry detergent, tea and coffee, utilities and group activities. Tenants, called “members,” can sign leases for less than 12 months; the company’s website lists one, three, or six months as options. The monthly rent for a private room with shared common space in existing developments ranges from $1,340 to $2,600; a room at the Richardson development will start at $1,700, according to the website.

An earlier owner consolidated the five lots into two larger ones. Each of those larger lots now contains what the current owners describe as two single-family dwellings, each of which has six bedrooms. According to city law, a “family” may consist of up to six unrelated people living together as a single housekeeping unit.

Mike Greenhalgh stands in his back yard as the new 24-bedroom development rises behind him on Richardson Place NW. (Michael S. Williamson/The Washington Post)

“The structures are properly designed, permitted, and constructed ‘Flats,’ which are matter-of-right uses for the site,” Peter Stuart, manager of OTD 410-412 Richardson Place LLC, which owns the property, said in an email.

To neighbors, however, it’s a dorm for grown-ups. They say the development should be considered an apartment building, rooming house, or membership organization, any of which by right could occupy a maximum of 40 percent of its lot in an R-4 zone. As a pair of two-family dwellings, however, it can occupy up to 60 percent, which the development does.

“Slice and dice it however you want, it’s a rooming house,” said Jim Norris, whose house abuts the property. He said the situation is particularly galling to him because he sold one of the lots that now make up the development, a move he regrets. “It’s made my life absolutely miserable.”

Neighbors worry that the 24 tenants could mushroom into 48 as girlfriends and boyfriends move in. (Common’s website says it welcomes individuals or couples.) They say street parking, already tight in the area, will become more scarce if the new residents apply for residential parking permits; that the amount of trash generated will require commercial rather than residential collection service; and that having so many more people coming and going will kill the alley’s peace and quiet.

Brad Hargreaves, Common’s founder and chief executive, said the D.C. property “currently complies with zoning laws.” Despite the options listed on the company’s website for one- and three-month leases, he said the development will require a six-month minimum commitment and that month-to-month leases will not be offered. “We expect the majority of members will sign year-long leases,” he said in an email, adding that 70 percent of Common members in other cities are on 12-month leases and that most stay longer than a year.

Asked about couples occupying one room, he said, “In D.C., the law is that no more than six unrelated people can live in a home, and Common intends to comply with the laws of the District.”

But neighbors say occupants’ and guests’ comings and goings would be hard to enforce. “You can end up with nearly 50 people there, which is nearly five times the amount that live on this street now,” Greenhalgh said.

Common Living offers furnished, private bedrooms and bathrooms with shared kitchens and lounges, along with weekly cleaning service. (Michael S. Williamson/The Washington Post)

The property’s recent history has been spotty, neighbors said. After the basement level sat unfinished for a couple of years, becoming a breeding ground for mosquitoes, the previous owner in 2014 airlifted the preassembled structure onto the property in a day or two with no warning.

Since then, the current developer, Oaktree Development, “never really spoke with the neighborhood about what was going on,” said Michael Zgoda, a member of the neighborhood association. “They’ve never let us onto the property. . . . They’ll say, ‘We’ve always been open to the neighbors,’ they’ll tell you yes, but then when we actually try to go in it doesn’t happen.”

Hargreaves said Common and the developer had “worked closely” with the neighborhood association to address its concerns. “There will be a commercial trash service that services both homes, 410 and 412 Richardson Place,” he said. “It was at their request, and we happily agreed to it.”

As for parking, he said that while there are no restrictions on residential parking permits, the development will provide four off-street parking spots for the development, and added, “We expect the vast majority of members will use public transportation since the homes are a short walk from a Metro station.”

Greenhalgh and other neighbors said they have never spoken to anyone from Common.

Although they don’t harbor hope that the building will be removed or scaled down, neighbors said they hope their appeal will persuade the city to see the development as a larger entity and require the developer to apply for a variance to occupy 60 percent of the lot.

In that case, neighbors say, their input will be part of the process, and promises to address their concerns will have a better chance of being enforced. If the city decides it is an apartment building, rooming house, or membership organization, that could trigger additional requirements such as fire escapes, a certain percentage of affordable housing, and accessibility for the disabled.