Meltzer/Mandl to transform white elephant into masterpiece.

A graceful 21-story structure is replacing the 13-story white brick box at 211 East 51st Street (between Second and Third Avenues) and transforming it into a luxury residential building.

The new structure will be sheathed in a glass-curtain wall with pale green spandrel glass detailing, creating 72 luxury condominium units with setbacks that produce 36 private, seven-foot-deep balconies and eight private terraces. David Mandl, president of Meltzer/Mandl Architects, PC, is the design architect for the project.

Much of the design has been determined by the unusual circumstances of the location's split zoning, in which 50-feet of frontage is in a residential zone and 40-feet is in a commercial zone. When addressing these issues, the architects discovered that the building, which was built in 1958 and predates current zoning laws, was under-built according to the current allowable FAR, so their design provides for an additional eight floor roof extension that will be built "as of right."

The plan for 211 East 51st Street includes a medical center in the commercial zone, occupying the ground-through third floors. The residential portion at the front of the building will feature a dramatic entry way with a cantilevered glass canopy and up-lighting embedded into the sidewalk.

"This is a unique situation in which zoning laws dictated the design of the renovation, and the result is much finer than even imagined," said Mandl. "Initially, the dual zones created a conundrum for us. But through the process, we found several options, including an additional 19,000 s/f of buildable space, which we incorporated into the design. Among other things, the extra square footage enabled us to extend the height and create a truly elegant silhouette."

The original plan that Meltzer/ Mandl prepared was for a multifamily condominium conversion, which included the renovation of the lobby and upgrades to individual kitchens and bathrooms within. In the midst of that project, the property was acquired by Allied Properties and the architects were asked to prepare a new plan suitable for a luxury condominium new building. The current plan, which was embraced by the developer and approved by the New York City Department of Buildings, entails the removal of the exterior masonry structure, down to the steel skeleton, concrete floors and foundation.

In addition to a dazzling modernist design that ties together a commercial and residential district, the building is bordered on one side by Green Acre Park, a "vest-pocket" public space with an award-winning design by Hideo Sasaki that includes a 25-foot waterfall. Built in 1971, the park's lush green foliage surrounds portions of 211 East 51st Street. The architects are replicating the park's distinct red brick pavers featured along its border wall and continuing them along the sidewalk on entry plaza of the building.

Infrastructure features include floor-to-ceiling windows composed of Super Low E glass, comprising high efficiency double glazed windows that reduce heat loss in the winter and heat gain in the summer.

A cooling tower with fan coil units will provide central air-conditioning. Additional amenities for the building will include a roof deck, club room, sundeck with outdoor pool, and fitness center. The sales and marketing agent for the building is Prudential Douglas Elliman.