At the turn of the last century, the industrialist Andrew Carnegie offered grants for 67 library branches in New York City, a boon for book-lovers across the five boroughs. More than a century later, however, many of these aging buildings are more than a little dog-eared, and the New York Public Library has been working to reclaim them as bright community hubs. The latest of these spaces to be revived, the St. Agnes Library on the Upper West Side, is back in shape after a two-year, $9.5 million restoration that library officials see as a model for the system’s Carnegie legacy. Originally designed by the New York firm Babb, Cook and Willard, the 1906 building had suffered typical alterations: Dropped ceilings occluded architectural details, and skylights were covered over, dimming interior reading rooms.

The main goal for Helpern Architects, commissioned for the renovation, was to recreate the original volumes of the nearly 18,000-square-foot structure. According to architect-in-charge Margaret O’Donoghue Castillo, the team found much ornament intact: When restoring the ceilings, original crown moldings were uncovered, while wood flooring and pillars could also be saved. Original windows had been removed, partly replaced by solid aluminum panels, so the architects specified new multipane mahogany windows, based on historic details.

Bringing the library into the 21st century also included making the building fully accessible. One of the main challenges was the new entrance ramp, which had to fit within both the landmark district and the Renaissance Revival facade, which fronts on Amsterdam Avenue. Using a reconstructed historic wrought-iron fence on the exterior, the ramp continues inside the building, minimizing its visual impact. To route new infrastructure, the firm took advantage of empty duct shafts that could be used for mechanical systems. And by tucking the elevator in back and inserting a fireproof glass stairwell, the structure’s grand marble stair could be retained as the center of attention. “The whole idea was to make it all feel seamless,” said David Helpern, founder and president of Helpern Architects. “The library had always been as you see it, yet it is new and modern.”

Among the new elements, a collection of colorful, egglike seats in the children’s section is illuminated by a new skylight, while a mural fills the entire south wall, inviting visitors within. The genesis of the wall graphic, spelling the word Imagine, was to capture the essence of the neighborhood, with Central Park’s Strawberry Fields and the Dakota Apartments, home to John Lennon, a stone’s throw away.

This successful blend of past and present has made St. Agnes a template for future library renovations. “This is the single best renovation of a Carnegie library I have ever seen,” Paul LeClerc, president of the New York Public Library, told AN. “I appreciate the way Helpern Architects have preserved the original aesthetic of these gorgeous, vivid spaces,” LeClerc continued. “You know you are in a historic building­–it’s welcoming and warm­. At the same time, it has the feature of our best contemporary buildings: lots of light coming in.”