Through much of the region’s building boom of the past few years, the sites of the city’s post-war residential developments, with their trademark brick and concrete towers adjacent to spacious courtyards and plazas, have been relatively devoid of major changes.

That could soon change: New plans by a Manhattan developer and a recent city initiative suggest that the generous open spaces below, around, and between the hundreds of such towers may become the next frontier for development in a city where a large swath of buildable land is an endangered species.

From their parking lots to basketball courts to large courtyards, these public and private modernist-style developments were designed with generous amounts of open space compared with the build-to-the-property-lines style that characterizes much of the city today. While builders generally have not yet begun to fill in the gaps on these sites, many urban planners and real estate analysts say their potential could soon be realized by developers. They praise the possibility for the vibrant street life such construction could create while cautioning about the perils of removing precious open space.

“The market is so tight at the moment that people are looking for it, and they’re going to find places where this is allowable,” an expert in urban development, Alex Garvin, said of the potential for development on these sites.

When Manhattan’s hallmark residential complex, Stuyvesant Town and Peter Cooper Village, was sold last fall for $5.4 billion, many speculated that buyer Tishman Speyer would have to build new structures on the site to make a satisfactory return. Similar speculation followed the giant $1.3 billion bid made for Brooklyn’s Starrett City complex by Clipper Equity in February.

A spokesman for Tishman Speyer said the company has no plans for development at Stuyvesant Town or Peter Cooper Village.
One of few developers known to be building on these sites, the Chetrit Group, filed for building permits late last month for two new residential towers to go in place of tennis courts on the Upper West Side. The courts, on the east side of Columbus Avenue between 97th and 100th streets, are part of a seven-building residential development built in the 1950s that spans between Amsterdam Avenue and Central Park West.

The plans for the new buildings mark a broader effort to do infill development on the large site, known as Park West Village. The Chetrit Group is already constructing a 29-story residential tower across the street, and has filed for another building at 100th Street and Amsterdam Avenue.

A vice president at the Chetrit Group, Jeffery Gdanski, would not discuss specifics of the 14- and 15-story towers planned for the tennis courts, though he said the group sees an opportunity to add vitality to the area, given that the buildings will be mixed-use.

“I think in general, when there’s underutilized space, I think it’s best to do something similar to what we’re doing, and bring retail and pedestrians and add life,” Mr. Gdanski said.

In an attempt to find more sites for new “affordable” housing, the city put out bids in December for 600 units of such development on the sites of public housing projects. A spokesman for the city’s Department of Housing Preservation and Development, Neill Coleman, said the units are planned on four sites and would be built over parking lots and a basketball court, a move that comes as the city has seen its stores of vacant land for affordable housing dwindle significantly over the past few decades.

“That inventory is pretty much exhausted now, so we’re looking for new sources of land,” he said, adding that the program will likely expand to other sites of city-operated housing complexes.

For urban planners and architects, the possibility of infill development on the residential complexes recalls a debate from decades ago in the planning community. In the 1950s and 1960s, planners and officials such as Robert Moses favored modernist developments, with sky-high towers and courtyards on super-blocks, designed to provide the poor and middle class with both housing and open space in one package.

Ever since, the tide generally has turned away from such developments, favoring critics such as Jane Jacobs, who advocated that traditional mixed-use, dense development on small blocks creates a vibrant street life that was mostly missing from the housing projects of the 1960s.

A principal at the architectural firm Ehrenkrantz Eckstut & Kuhn, Peter Cavaluzzi, said he believes owners of residential complexes are beginning to see the potential for building on the sites, which could bring more vibrant street life to many areas where it is absent.

“It’s one of those instances where I think development interests, which are generally after financial reward, and good urbanism or good architecture — there’s a nexus,” Mr. Cavaluzzi said.

However, developers “certainly could go overboard,” he cautioned, as there are many vibrant courtyards in places such as Stuyvesant Town where development could harm the atmosphere.

While many urban planners say the potential for this new development is likely, the owners of residential complexes have generally not yet been building anything new on the sites.

“Many of those properties are strong and economically viable in their current configuration, and I think that’s taking on a new level of risk,” a vice president at the Real Estate Board of New York, Michael Slattery, said.

Zoning and other regulations add further barriers to many sites, including caps on density and changes to a site plan that would require approval of the City Council.

Developers would also be likely to face significant opposition from tenants of a complex where development is proposed, as new buildings can alter the shadows and planned open spaces of the sites.

A former president of the tenants’ board at the Chetrit Group’s development, Vivian Dee, said the sections of the complex on either side of Columbus used to feel like a village. Today, the company’s planned 29-story tower on the west side of Columbus is being constructed atop a parking lot and entranceway to the western half of the complex, sectioning off the two halves of the development.

“What they’re planning to build is a wall on Columbus Avenue,” Ms. Dee, who was upset to learn of the new towers planned for the tennis courts, said. “This changes the whole tenor of the community.”