The days of developers using mechanical voids to boost their buildings’ heights may soon be coming to an end. The Department of City Planning has proposed an amendment to New York’s zoning code that would make those voids—ostensibly used to store mechanical equipment, but often occupying space that’s much larger than necessary—count toward a building’s overall allowable size.

Under the current zoning code, there isn’t much in the way of restrictions on mechanical voids; they’re excluded from a building’s floor-area ratio (which determines how much space a building can occupy within its footprint), and there are no height limits for those spaces.

DCP has proposed making those voids count toward a residential building’s total FAR when they’re taller than 25 feet high, or when those floors are located within 75 feet of one another. While the rule is intended to apply to residential buildings, there are some cases in mixed-use buildings—if the non-residential section is less than a quarter of the structure’s usable space, for instance—where it may apply. Mechanical bulkheads on the top of buildings would be exempt, detailed Kiyoshi Yamazakia, a city planner with DCP, at Monday’s City Planning Commission (CPC) meeting.

“We believe that for a building to function efficiently the mechanical space needs to be distributed evenly so that you don’t need to have piping that goes 20, 30 stories up in the air,” said Yamazaki.

The goal, according to DCP’s amendment application, is to “discourage the use of excessive mechanical floors to artificially increase building height by limiting the height and frequency of such spaces incorporated into a building’s design.”

Courtesy of the Department of City Planning

Although this practice has been commonly used by developers in recent years—220 Central Park South, for instance, has several mechanical floors that range from 18 to 24 feet in height—it wasn’t until last year, when a proposal for a Rafael Viñoly-designed “building on stilts” on East 62nd Street, prompted backlash from neighborhood groups. The proposed design included 150 feet of mechanical void stuck in the middle of the tower, and spurred the de Blasio administration’s interest in curbing how those spaces are used.

But earlier this month, DOB told Extell that it would revoke its building permits unless the developer could give a reason why the void is necessary. Extell chief Gary Barnett told the New York Times that if the project can’t move forward, the firm may bring a lawsuit against the city since it is attempting to apply restrictions that do not currently exist.

City Planning Commissioner Anna Hayes Levin praised the city for taking action to curb the misused spaces.

“I’m pleased to see this rule moving forward I know its been a topic on many people’s mind for some time,” Levin said during Monday’s CPC hearing.

“There just seems to be something odd about a manipulation of the zoning resolution in a way that allows people to monetize the sky, which really belongs to all of us.”

Source: ny.curbed.com