Brett McEnroe, 49, of Dover Plains, and Roy Powell, 51, of New Paltz, were working on a planned expansion of the Redeemer Presbyterian Church on Manhattan's Upper West Side as members of a four-person crew, authorities said.
The city's buildings commissioner, Robert LiMandri, said it appeared the workers did not have proper fall protection, including harnesses, safety netting or a support platform. The church expansion began in 2009, with no mishaps reported until now.
He called the deaths "a tragic reminder" of the need to observe safety measures in the construction industry, and said the city would be investigating why the men were not equipped properly.
The commissioner issued a stop-work order for the building on West 83rd Street.
The workers were pronounced dead at hospitals after a 911 call at about 10:30 a.m.
Redeemer Presbyterian Church did not immediately respond to an Associated Press request for comment .
Four construction workers fell to their deaths in New York City last year.