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New York looks into voids used by builders to bend height rules

New York City Council member Ben Kallos worries that without intervention, the mechanical voids in the city's tallest residential skyscrapers will just keep growing.

New York

AT the heart of many of New York's tallest residential skyscrapers lie "mechanical voids". They are growing in size and number and the city council and Mayor Bill de Blasio have had enough.

From outside, they are often just windowless strips covering the equivalent of multiple floors. Inside is equipment to keep the building running, and empty space, sometimes a lot. Height added by mechanical rooms doesn't count toward a tower's floor area that developers must get approved by the city, so they can be used to make buildings taller. With greater height comes more expensive penthouse views and the bragging rights that come with stature.

Critics see the practice as potentially dangerous, forcing firefighters or medical workers responding to an emergency to cover much greater distances - sometimes unanticipated, since the voids aren't numbered floors.

"It is a symptom of everything that is becoming wrong with our society that developers would rather build empty spaces in buildings for billionaires than affordable housing," said New York City Council member Ben Kallos. "We're not saying that you can't do this. What we're saying is that if you have a limited amount of floor area that you can use to put up a building, then you have to use that floor area."

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An amendment filed by the planning department at Mr de Blasio's request would limit mechanical spaces to a height of 25 feet, and require multiple mechanical floors to be at least 75 feet apart. Otherwise, they would count toward the building's floor area as set by zoning rules, which determine how tall a building can be.

Mr Kallos worries that without intervention, the mechanical voids will just keep growing - to 300 or 400 or 500 vertical feet of dead space. The practice is especially noticeable on Billionaire's Row - a strip of super-luxury condo buildings just south of Central Park. Mechanical voids make up about a quarter of 432 Park Ave, Manhattan's tallest completed condominium tower, according to Mr Kallos. The building's minimalist boxy design can be seen from every borough.

The city's amendment is a move in the right direction, but leaves too much wiggle room, Manhattan Borough President Gale Brewer said during a public meeting. It doesn't address unenclosed spaces such as terraces, and would affect only parts of the borough, leaving out specific parts of Billionaire's Row, which she said "is facing an imminent threat". BLOOMBERG

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