The Arlington County Board voted unanimously Saturday to spend $27.1 million on a seven-story building near the courthouse that will provide office space for county employees and a year-round homeless shelter, an addition that has angered nearby residents.

Most of the floors at 2020 14th St. North will be dedicated to county office space, but two floors will offer about 50 beds for single adults, five medical respite beds and another 25 spaces during winter months, as well as space for programs intended to get people into permanent housing.

While homeless advocates said they were thrilled by the decision, residents of the adjacent Woodbury Heights condominiums objected, calling the shelter residents a threat to their safety.

“You’re shoving this down our throats,” said January Holt, one of the residents who has been opposed to the proposal since it first became public a year ago. “You guys trespassed on our private property last Saturday with a surveyor . . . I’m enraged, disgusted and it’s just plain wrong.”

Kenneth Robinson, president of the 170-unit condo association, said 20 units in the building have sold in the past year, twice the previous rate, and other owners are renting their apartments out because they are unable to sell. He cited national statistics that showed homeless shelters disproportionately house sex offenders, and asked the county to promise that violent criminals and sexual predators would be banned from the building. He also asked that 24-hour security be provided on site.

Advocates for the Arlington Street People’s Assistance Network, which has operated the current emergency winter shelter a block away for the past 20 years, said they’ve never had a problem with violence, a position that local police agreed with, said Barbara Donnellan, the county manager. Homeless people who show up for meals at Central United Methodist Church once a week coexist without problems in the same building as a daycare center, said the Rev. Richard Cobb.

“In those five years, we have not had problems and our property values have not decreased, they’ve increased,” he said. “The homeless respect and listen to us because they don’t want to lose these services. Folks who have these fears [about the homeless] are not involved. Those who are involved don’t have these fears.”

The building sale will close Nov. 20, and the county expects to spend about $15 million on design, reconstruction, equipment and contingency fees. While the three street-level retail stores currently there will be offered leases to stay, the 18 offices above them will eventually have to move. The county set aside $2.5 million to help relocate those tenants.

Before the shelter can begin to operate in the new space, a special use permit is needed. County officials said they will hold three meetings with residents in December and January to try to address their concerns in the permit rules. A County Board vote on the permit is tentatively set for March.

“This board does not turn a deaf ear to people feeling safe in their home,” said board chair Mary Hynes. “No one is interested in creating unsafe conditions for anybody in the community.”

But residents said their concerns have been ignored for the past year and they’ve had difficulty getting appointments with board members. One resident was told he would have to pay $17,000 in fees for public documents related to the purchase of the building.

Board members and staff said they needed to purchase the 14th Street building because the existing office space and the winter-only shelter could not be brought up to code and both were seriously outdated. Adding a women’s shower or repairing an elevator were major undertakings.