On May 29, 2019, the City Council adopted a zoning text amendment to count certain mechanical voids as zoning floor area in residential towers.

The amendment does not prohibit any mechanical space outright; instead, it requires that mechanical floors exceeding a height of 25 feet be counted as zoning floor area. Additionally, such mechanical floors will count toward zoning floor area if they are located within 75 feet of one another and exceed 25 feet in height in the aggregate. Above the 25-foot threshold, the number of stories of floor area is calculated by aggregating the total height of such spaces, dividing by 25 and rounding to the nearest whole integer. For example, a 40-foot mechanical void would count as two floors of floor area (40/25 = 1.6, rounded to the closest whole number equals two).

The amendment applies where residential towers are permitted, i.e., in noncontextual R9 and R10 zoning districts and their equivalent commercial districts, as well as in special districts in which the underlying R9 and R10 tower regulations apply.1 The new provisions do not apply to special districts with alternative tower regulations — such as the Special Midtown, Lower Manhattan and Downtown Brooklyn districts — though the Department of City Planning (DCP) has promised a follow-up proposal by the end of this summer with respect to those areas.

The new restrictions apply to residential towers, as well as to mixed-use buildings where nonresidential uses occupy less than 25% of floor area. Mechanical penthouses, below-grade mechanical space and unenclosed spaces such as rooftops or terraces are not regulated by the amendment.

DCP has also promised to study, within the next year, further regulations regarding unenclosed spaces that are not currently counted as floor area. 

State Legislation Also Proposed

In addition, the State Assembly has introduced legislation to impose new regulations on building heights through amendment of the State Multiple Dwelling Law. The bill, No. 5026A, would change the definition of "floor area" to include two, three, four or five times the actual amount of floor space, depending on the height, of any dwelling space with a floor-to-ceiling height exceeding 12 feet (except that ground floor space up to 20 feet in height would be counted only once). The bill would also include as floor area all mechanical space in excess of 5% of the gross floor area of a building, as well as certain open areas located under portions of a building. The bill is currently before the Housing Committee and has 31 co-sponsors.


1 Noncontextual districts are those without a suffix (e.g., an R9 district, but not an R9A district).

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