The building at 93 Reade Street was redesigned by WORKac

A famed cast-iron building at 93 Reade Street in Tribeca has a secret addition that isn’t visible from street level—and that was essentially the directive architecture firm WORKac had to work with when they were hired, in 2015, to reconfigure the interiors of this over 150-year-old building into four condos. Their work on Obsidian House, as the condo building is now known, is a subject of a recent New York Times Style Magazine piece.

WORKac, which is comprised of the husband and wife team of Dan Wood and Amale Andraos, was tasked with creating a penthouse addition to the building, which was originally built in 1857. They had one major problem however. The building is located within a historic district, and if the developers, Knightsbridge Properties wanted an addition, they would have to ensure that it wasn’t too tall and would not be visible from street level.

WORKac started innovating—they thought of a structure that would be shorter in the front, and taller at the back, and to deal with a low ceiling level they decided to lower the floor slightly into the floor below. And then they added the jagged, origami-shaped roof—resembling a piece of obsidian, which is where the building gets its name from.

The building features three loft-style apartments aside from the triplex penthouse, the latter of which sold for $7.92 million just about a month ago. The original cast-iron building was built by brothers Joshua and John Q. Jones, from whom the phrase “keeping up with the Joneses,” originated.

 Bruce Damonte/T The New York Times Style Magazine
An aerial view of the glass penthouse at 93 Reade Street