On a cold day, about 50 homeless men and women gathered in a circle at the Lamb Center in Fairfax City to pray before a lunch of donated pizza. Candles lit for Bible study flickered at a long communal table. Washing machines churned in the corner. Worn duffle bags and belongings were stashed in every available inch of space — even stacked in nearby offices.

For more than a decade, the Lamb Center — sponsored by about 50 local churches — has been one of the few places in Northern Virginia where the area’s homeless can gather during the day for job counseling, food and a hot shower or to do a bit of laundry.

But in the past five years, the number of clients has almost doubled, from 60 to more than 100 a day — so many that they are barely able to squeeze into the small office building just off the city’s gateway on Fairfax Circle.

The center’s prominent location has long been a source of controversy.

City officials say they’ve spent years grappling with neighbors’ complaints about noise, loitering and drunkenness. In 2008, the city said that some of the center’s activities, such as offering laundry services and meals, violated ordinances and slapped it with zoning violations, which are pending. Now, Lamb officials say, the city plans to tighten its zoning code in ways that will make it difficult, if not impossible, to move to roomier quarters.

“The mayor has made it clear he doesn’t want us in this location,” said Dave Larrabee, the center’s director. “He has development plans for the circle. They’ve always said they prefer we be off the major thoroughfares.”

Fairfax City officials say that the proposed regulations — which could be approved by the City Council as early as Tuesday — do not target Lamb. The rules would require any social service agency moving into new space to apply for a special permit, which would give neighboring residents and businesses a chance to weigh in.

“It seems like the emotion that always gets attached to this kind of discussion is so blown out of proportion and unfair to the city of Fairfax,” Mayor Robert F. Lederer said. “It’s unfortunate.

“This is not an indictment of the Lamb Center. We’re simply saying that when a social services provider wants to relocate in the city, the community should be a partner in the discussion.”

According to estimates from the Metropolitan Washington Council of Governments, Fairfax County had a homeless population of about 1,500 last year, down slightly from the previous year, but still the largest population of homeless outside of the District’s 6,500.

The county has seven homeless shelters — four for families and three for singles — that are “always full and always have a wait,” said Toya Codjoe, program manager at Fairfax’s Office to Prevent and End Homelessness.

James Ware, 52, a medical technician who lost his job and his apartment a year ago, said he often spends his days at the Lamb Center. Finding a bed is sometimes difficult, he says, so he often camps in nearby woods.

“It’s a great place to come when you’re trying to get yourself together,” he said.

The Lamb Center was founded in 1992 by Truro Church and is an independent, nonprofit organization backed by about 50 local churches. It’s one of the only daytime drop-in centers in the region, Codjoe said.

But neighboring businesses have said that the men and women have no place to go after the center closes at 3 p.m., so they linger in nearby restaurants or camp in neighboring woods and streambeds.

“It’s a concern we are constantly dealing with in one fashion or another,” said Robert Sisson, the city manager. A six-month survey in 2009 found that in 40 percent of the arrests around Fairfax Circle, suspects said that they were homeless or listed the Lamb Center as their address.

Having a cramped homeless center steps from Fairfax Circle also puts a damper on hopes for upscale development, business owners say. In 2008, the city approved a long-range plan for Route 50 — now an inchoate mix of aging strip malls and car dealerships — that calls for turning the busy road into a “classic boulevard,” a “walkable great street” lined with sidewalks, trees and restful public spaces.

Lamb is in “the wrong location in a retail environment. It’s not helping anybody. It’s sad to say, but that’s the way it is,” said Joe Lothrop, whose family has owned the land behind the center since 1942 and is building an 18,000-square-foot retail center there.

He said that his tenants clean up discarded liquor bottles and drug paraphernalia on a daily basis and that some patrons are frightened by the men who gather outside.

Attempts to move the center to a different space have failed. In 2007, when the city tried to buy a building outside its limits in Merrifield where the center could be moved, the plan collapsed amid vehement opposition from Merrifield residents.

Lamb Center officials say they feel stuck: If tighter regulations are enacted, they will have a harder time moving to a new building; if they stay in their cramped quarters, they may have to do away with services such as hot showers and meal service — depending on the resolution of the pending zoning citations.

If the center closed its doors or moved, “it would be terrible,” Ware said. “I’d probably go hungry.”