A feud over the future of Philadelphia’s last grain elevator has come down on the side of preservation instead of adaptive reuse, after developer Pearl Properties bowed to pressure from community and preservation groups last month and ditched an eye-popping plan to turn the Reading Company Grain Elevator in Center City into a mixed-use development.

The fortress-like concrete structure on the corner of 20th and Callowhill streets was built by the Reading Railroad in 1925, replacing an older wooden granary that had burned down on the same site. After going out of commission in 1950, it stood empty until an interior designer built penthouse offices above it in the 1970s, and in 1982 it was listed on the National Register of Historic Places.

Pearl Properties hired local Interface Studio Architects to renovate the granary in 2007 and find a way to adapt it as a mixed-use development that would join a wave of new projects in the surrounding neighborhood. The building posed an exciting challenge for Brian Phillips, founding partner of ISA. The first two floors and a penthouse level are separated by a grid of 72 six-story grain silos, making 80 percent of the structure uninhabitable. “A building like this has very little future if you can’t change it, in our opinion,” Phillips said.

The plan he put forth earlier this year would have had retail, restaurants, and a lobby on the first two floors, silos occupying the equivalent of floors three through eight, and twelve stories of condominiums above that, which ISA had been considering building out of prefabricated metal steel boxes. A green-wall “wrapper” would have run up the side of the granary, cradled the middle penthouse level, and then continued up the opposite side of the building to hold the modular box apartments, tying the old and new together.

The silos themselves would have been put to environmental and recreational ends, Phillips said. One silo alone would have been enough to store rainwater for a year. Other silos in the interior of the building, insulated from the outside, would have been used to create a geothermal system to funnel the soil’s cool temperatures upward in summer, and heat the structure in winter. Another silo, positioned above the second-floor fitness center, would have been opened up from below so that people could scale it as a climbing wall.

But ISA’s ambitious proposal was panned by The Philadelphia Inquirer and by preservationists such as the Preservation Alliance, who saw the plan as hostile to an important piece of Philadelphia’s industrial heritage. “Our reaction when he showed us the proposal was extremely negative,” said John Gallory, president of the Preservation Alliance.

Pearl Properties president Jim Pearlstein, who did not respond to requests for comment, is now planning a minor renovation that preserves the essential structure of the granary as-is. He has dropped ISA from the project, according to the architects, and will be hiring another firm to design condominiums on a lot adjacent to the granary.

“We’re very pleased they abandoned the proposal,” Gallory said. “This is a rare example of a developer being sensitive to the community’s wishes.”