Wall Street titan’s $80M bulletproof UES mansion could set Manhattan townhouse record

Former Morgan Stanley honcho John Mack and his wife, Christy, have put their converted Upper East Side carriage house on the market for a jaw-dropping $80 million, making it the most expensive townhouse currently for sale in New York City.

If a buyer pays up, the deal would smash the borough’s townhouse record, set in June 2019 when 14 East 67th Street, a 22,000-square-foot mansion, traded for $77.1 million.

“If this listing ends up selling for $80 million, it would be the highest Manhattan townhouse sale on record,” appraiser Jonathan Miller of Miller Samuel told The Post.

“If any home deserves that record, it’s this one,” listing agent Mike Fabbri of The Agency told The Post.

The Macks scooped up 165 East 70th Street for $13.5 million in 2009, according to property records, back when John was still steering the Wall Street giant. At the time, the 33-foot-wide building had never been a home at all.

“It was a distressed property,” Fabbri said. “It was always used as a garage.”

What followed was a six-year gut job, with Christy leading the design, according to Fabbri. The couple kept the landmarked limestone facade, added a floor and reinforced the guts with steel beams, transforming the bare-bones stable into a roughly 16,000-square-foot mansion with 20 rooms.

“It took our client six years to do this and build this,” Fabbri said.

The Macks had hunted for roughly a decade for a move-in-ready townhouse before settling on building their own, he said. Now the couple is cashing out and retiring to North Carolina, where both grew up.

John, who led Morgan Stanley as CEO through the 2008 financial meltdown, gave up the chairman’s seat in 2011.

Security was baked in from the start, down to a bulletproof front door, a state-of-the-art alarm system and dedicated security offices.

“I think everything was thought of in this home, even safety and security,” Fabbri said, adding that the house was “built like a fortress.”

The creature comforts are just as serious. A snowmelt system keeps the sidewalk clear in winter.

“So when it snows outside, the sidewalk in front of the house melts away the snow,” Fabbri explained.

Inside, the radiant heat runs everywhere. “Not just the bedrooms and the baths, like every single floor is heated,” he said. The HVAC was swapped out this year.

The cellar works as a private wellness club with a hot tub, cold plunge, steam room, sauna and massage room. There’s a 13-seat screening room, a wine cellar for 6,319 bottles, two elevators (one of them high-speed), six wood-burning fireplaces and three landscaped terraces, including a 480-square-foot perch on the roof.

Then there’s the rarest Manhattan luxury of all, a private curb cut leading to a garage that doubles as party space.

“You’re usually giving up something to live in a townhouse,” Fabbri said. “You’ve got it all in this house.”

The building dates to 1902, when society architect C.P.H. Gilbert, the talent behind some of Fifth Avenue’s grandest mansions, designed it for banker Henri P. Wertheim.

“It’s not like you can recreate a C.P.H. Gilbert home,” Fabbri said.

Only five owners have held the keys in more than a century, according to Fabbri. The roster includes Singer sewing machine heir Stephen C. Clark and Paul and Bunny Mellon, who used it as a private garage before selling to the Macks.

Rather than erase the building’s horse-and-buggy past, the renovation worked it right into the design. The old ramps, scarred by decades of hooves, turned out to be slabs of virgin chestnut. They now wrap the lower-level gym as wainscoting.

For Fabbri, the real selling point is that the next owner won’t have to lift a finger.

“It’s completely turnkey, which is the magic word,” he said. “It’s not just a showpiece, which it is. It’s also somewhere that’s really functional.”