Peter Pelsinski recalls how, some years back, longtime client Stephen Sullens “made an offhand remark that he’d love to find a place on Gramercy Park” to himself and Karen Stonely, who together oversee New York–based SPAN Architecture. “That stuck in the back of our brains,” Pelsinksi adds. So when a colleague “mentioned the possibility of this structure going to market, we told Steve.” Sullens and his wife, Allison, closed on the historic property in 2017.

After the Greek Revival home’s first owner died in 1869, his family held onto the house until 1923. They even improved upon the property, commissioning Stanford White to transform its parlor-level dining room into a mahogany-and-oak salon. Yet their successors were not nearly as stewardship-minded. White’s millwork, for one, was covered in white paint. And as the building was chopped into seven dwellings, water from careless plumbing jobs compromised structural members. The Sullenses invited SPAN to reconstitute the house as a single-family residence, a task that involved excavating the cellar and backyard, introducing an elevator, and installing new systems across 10,000 square feet.

The new homeowners also wanted the result to feel useful and inviting, rather than museum-like. “One of the things Steve and Allison said from the beginning is they wanted the house to be memorable spatially, but they didn’t want it to be ostentatious,” Stonely explains. Stephen concurs: “This whole project started as a search for our family home—we wanted to entertain and celebrate music.”

While planning the modernization, SPAN in turn reorganized key portions of the house to suit the Sullenses’ living patterns. For example, Pelsinski, who collaborated with Anne-Marie Winter and Christiane Duncan on the renovation, says, “We needed a new open kitchen, and we wanted to make it at the garden level as a place where the family could gather.” To realize this goal, SPAN eliminated an apartment kitchen at the parlor level, which had been located on one side of the salon. The architecture studio then removed that old kitchen’s footprint altogether, creating a double-height volume for the dining area in the new kitchen below. A soaring window links this atrium-like space to the rear garden visually. Daylight and views also reach into the salon through a reinstated archway in the room’s north wall, for which SPAN created a balustrade.

Karen Stonely explains that she and Pelsinski are strong proponents of biophilic design, and that their restacking of the kitchen and salon is just one instance of “making sure you were always fully aware of your connection to the landscape.” The guiding principle yielded other changes at various scales.

Perhaps most notably, SPAN transformed a necessary new roof into a lush open-air room, which it realized with the help of New York–based landscape architecture firm RKLA Studio as well as Los Angeles artist Robbie Simon, who created a mural for the bulkhead. (In addition to biophilia, “We’ve always been interested in building great collaborative teams,” Pelsinski says of the group behind the rooftop oasis.) Smaller yet equally important examples of landscape connectivity include the insertion of a skylight above the main staircase, and the alignment of interior openings to the outdoors.