It was business as usual when I stopped at the Queens Central Library in downtown Jamaica the other morning. Visitors were nosing through racks of dog-eared best sellers, schmoozing near the circulation desk and peering into banks of computers on long tables in the lobby.

Across the room, beneath “Discover!” in red lettering, light poured through a large candy-colored doorway opening onto a new addition, a children’s science center. Immaculate and all white, the place gave off the cheery, vaguely techno vibe of a Swatch shop on the Ginza.

Designed by 1100 Architect with an interior by Lee H. Skolnick Architecture & Design Partnership, the Children’s Library Discovery Center, as it’s called, is part of a quiet revolution reshaping the city’s public architecture. Piecemeal across the five boroughs, New York is gradually being remade.

These changes come largely thanks to David J. Burney, a polite Englishman who has lived here for 30-odd years and, since 2004, has been Mayor Michael R. Bloomberg’s commissioner for the Department of Design and Construction. Under him, and mostly under the radar, dozens of new and refurbished libraries, firehouses, emergency medical stations, police precincts, homeless processing centers and museums have been designed by gifted and occasionally famous architects. Taken together, they have brought fresh architectural standards to the city’s infrastructure and, often, to poor, middle- and working-class neighborhoods that have long been overlooked.