Conversions Eliminated Over 100K Housing Units in New York City

Apartment-to-house conversions are contributing to a net loss of housing in some of the city’s historic neighborhoods.

1 minute read

August 28, 2023, 5:00 AM PDT

By Diana Ionescu @aworkoffiction


Colorful historic brownstones in New York City

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According to an article by Rachel Holliday Smith in The City, “over the last 70-plus years, mergers of flats and rooming houses into bigger residences have taken a steady toll on [New York City’s] housing stock, a new study finds.”

The study from historic preservationist Adam Brodheim found that in Manhattan, where conversions have been most aggressive, “each conversion accounted for the loss of between six or seven units on average.” Based on Brodheim’s estimate, the city lost 104,000 housing units to conversions since the 1950s.

“In the past decade, such apartment combinations have nearly erased gains made by the construction of new housing units in the wealthiest parts of the city, particularly in the Upper East and Upper West sides of Manhattan.” The city’s historic districts also experienced a net loss of housing between 2010 and 2022.

The answer, for Brodheim and others, is not to limit conversions, but to make up for them.“Trying to restrict that activity is not necessarily beneficial because there is a demand for it. What this illustrates is that you just have to build a lot more housing.” 

Thursday, August 24, 2023 in The City

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