Ms. McCabe said she was not sure why it had taken so long for the agency to conduct its inspection, but noted, “We don’t want to see more young people on the street.”

That, however, was happening. A young man who was at Sylvia’s Place on the night of the inspection, who spoke on the condition of anonymity in order not to alienate the shelter’s administrators, said that on previous nights, 20 or 30 people were sleeping there, though there were only “about five cots, and about six pillows” for them.

After the agencies showed up, he said, Sylvia’s staff allowed only six clients to stay the night. He said he voluntarily left with friends and went to Zuccotti Park, where he spent the rainy night with Occupy Wall Street protesters.

The next day, he was grim about the prospect of having to sleep outdoors again. “It’s my birthday,” he said, “and I was hoping my friends and I could rent a motel room or something, so I could just sleep inside on my birthday.”

Mr. Siciliano said that the homelessness of young L.G.B.T. people stands in stark contrast to recent gay-rights successes like the repeal of the military’s “don’t ask, don’t tell” policy and the passage of the same-sex marriage bill in New York.

Though he called attention to the conditions at Sylvia’s Place, he said that they paled in comparison to the much bigger problem he saw facing homeless youth in New York: “The utter negligence by the city and the state.”

He recently began a Campaign for Youth Shelter that calls upon the government to finance an additional 100 shelter beds every year, at an annual cost of $3 million, until there are enough shelter beds for all homeless youths.

From the Green Chimneys office in the South Bronx, Ms. Nolan acknowledged the conundrum that Sylvia’s Place faces. “It’s really hard to find space. I understand that,” she said. Still, she maintains, “it’s important to find the right space that’s safe, appropriate and healthy” for housing anyone — “even if they’re homeless, even if they’re gay.”