Trinity appears to have it all: a vibrant congregation, well-tended church buildings, a shiny new tower promising robust amenities — and abundant resources.

In some respects it might even resemble the megachurches of the suburbs, with their broadcasting stations and satellite churches to which they beam the Sunday service. Trinity’s own broadcast room is being updated in the renovation, as are other back-of-house spaces. A large split-screen monitor in the new sacristy will allow the clergy to track activity in the sanctuary as well as in St. Paul’s and in the parish-house portion of the new tower.

Could big, muscular churches become the new normal in New York as smaller churches vanish?

The Rev. Dr. Donna Schaper, of Judson Memorial Church in the West Village, certainly hopes not. Smaller houses of worship provide not only the beauty of their historic structures, she argued, but also crucial social services as well: soup kitchens, food pantries, art programs and gathering places for community meetings.

“We need help — technical assistance, policy relief,” Dr. Schaper said. She maintains it is a mistake when churches get into the real estate game on their own. The sale of air rights, she pointed out, has led to “gentrification and its partner, racism,” as demolished religious institutions are replaced by luxury housing, often resulting in the displacement of longtime neighborhood residents.

Judson Memorial, designed by Stanford White in the Romanesque style, with stained glass by John La Farge, is a designated city landmark and is listed on the National Register of Historic Places. The church is putting on a new roof after a $3 million fund-raising campaign, but it must turn around and raise $4 million more because it has heating issues and a broken elevator.

The elevator is a serious concern since worship takes place on the second floor. The church has removed the pews in the sanctuary allowing for “hyperuse,” as Dr. Schaper put it, by a variety of groups. (Rentals yield important revenue, making up over a third of Judson’s $1 million annual budget.) Judson provides services to 150 undocumented immigrants a week, among others.

Dr. Schaper has started a movement called Bricks and Mortals, with the goal of coming up with collective solutions so that no church has to go it alone. One idea is for the city to create an air-rights bank that would allow the rights “to be monetized, but not abused” — put into a bank for the development of affordable housing, for example.

“My fear is that the very thing that makes New York so lovely and interesting — the variety of our culture — is threatened by congregations becoming restaurants and high-end apartments. It’s almost as tragic as losing the beautiful buildings.”