NEW YORK | Residential Conversions

[NYguy]

Originally Posted by NYguy

https://www.pincusco.com/apollo-slg-rxr-file-plans-for-942-resi-units-in-5-times-square/

Apollo, SLG, RXR file plans for 942 resi units at 5 Times Square

The full redevelopment will feature over 1,200 apartments in a prime location on 42nd and 7th. A quarter of the units will be for affordable housing.

Never thought we would see this. This building was part of the renewal of Times Square, which doesn't seem that long ago.

[NYguy]

https://www.multihousingnews.com/david-werner-jv-eyes-manhattan-office-to-resi-conversion/


David Werner JV Eyes Manhattan Office-to-Resi Conversion
The partners have recently acquired the 32-story building.





By Vicentiu Fusea
April 11, 2025

The joint venture between David Werner Real Estate Investments and Metro Loft Management has conversion plans for 675 Third Avenue, a 32-story office building in Manhattan it recently acquired. The partners intend to repurpose it into a rental community with some 430 units.

Northwind Group provided a $90 million senior first-mortgage loan for the acquisition and predevelopment of the 342,000-square-foot property previously owned by The Durst Organization. The firm’s Northwind Debt Fund III, which launched this January, originated and structured the financing.

Located at 675 Third Ave. close to Midtown Manhattan, the high-rise is within walking distance of Empire State Building and Rockefeller Center. Central Park is 1 mile away, while JFK International Airport is 15 miles southeast.

Completed in 1966, the building underwent cosmetic improvements in 2014 and was completely renovated two years later. The Class A, LEED Gold-certified tower also comprises more than 10,000 square feet of retail space.

Last year, CommercialEdge developed the Conversion Feasibility Index, a Yardi-powered tool that assesses the possibilities of repurposing office buildings based on multiple criteria, including the property’s age, square footage and building depth, as well as walkability and transit accessibility. The high-rise at 675 Third Ave. scores 92, making it a strong candidate for redevelopment.

The joint venture is also working on the largest office-to-residential conversion in Manhattan: The adaptive reuse of Pfizer’s formal headquarters into more than 1,600 units. Northwind Group provided $135 million in financing for that project, as well as a $75 million first mortgage acquisition loan.

[NYguy]

https://commercialobserver.com/2025/04/david-werner-purchase-5-hanover-square-conversion/

David Werner Set to Buy 5 Hanover Square for Another Potential Resi Conversion





BY ISABELLE DURSO
APRIL 11, 2025

David Werner isn’t slowing down when it comes to office-to-residential conversions.

His namesake firm, David Werner Real Estate Investments, is in contract to buy the 25-story office building at 5 Hanover Square in the Financial District from CIM Group for between $50 million and $60 million, according to a source with knowledge of the deal. The Real Deal first reported the news.

It’s unclear what Werner’s exact plans are for 5 Hanover Square, but the property is about half vacant and “would most likely be a partial conversion” to residential, TRD reported.

News of the deal comes after Werner and Nathan Berman’s Metro Loft Management secured a $90 million loan from Northwind Group this week to acquire and convert the office building at 675 Third Avenue into approximately 430 residential rental units, as CO previously reported.

That deal is on the same block as Werner and Berman’s other conversion project of the former Pfizer headquarters at 235 East 42nd Street and the neighboring 219 East 42nd Street, which will be turned into roughly 1,600 combined rental units, CO reported.

And in February, Werner went into contract to buy the office building at 300 East 42nd Street from Fortress Investment Group for $52 million, with plans for another potential conversion to residential.

[NYguy]

https://www.costar.com/article/344172621...rs-former-manhattan-home-lands-financing

Office-to-residential project connected to Pfizer's former Manhattan home lands financing
Joint venture set to add 430 units next to largest similar development underway in New York City





By Andria Cheng
CoStar News
April 11,

[NYguy]

https://www.nytimes.com/2025/04/25/reale...esidential-building-conversion-soma.html

A Former Office Tower Goes Big for Residents
With 1,320 rental apartments and a host of amenities, 25 Water Street is the country’s largest office-to-residential conversion to date.





By Matt YanPhotographs by James Estrin
April 25, 2025

An office building in the Financial District has ditched cubicles and shed most of its original facade, making way for more than 1,000 new rental apartments and splashy amenities.

The building at 25 Water Street, now known as SoMA for South Manhattan, previously housed JPMorganChase, the National Enquirer and the New York Daily News. Co-developed by GFP Real Estate and Metro Loft, SoMA is the country’s largest residential building to be converted from offices to date, with 1,320 apartments. (Metro Loft and a partner are also converting the old Pfizer headquarters in Midtown, which will surpass SoMA with 1,602 apartments.)

Nathan Berman, the founder of Metro Loft, said that converting buildings removes “the millions of feet of space that are essentially obsolete.”

“They can’t compete as office buildings anymore, and we’re taking them, sort of, out of the race,” he said.

Conversions offer a significant challenge for developers, and with more than 50 units per floor, Mr. Berman compared SoMA to a puzzle. The original brick building resembled an IBM punch card, with windows scattered around the facade. The converted building has more windows and flourishes of the original brick along with a new 10-story addition on top, bringing it to 32 stories. “It was almost like doing a new building inside an old building,” said John Cetra, the co-founder of CetraRuddy, an architecture and interior design firm.

Studio apartments start at $4,000 per month, and three bedrooms start at $10,000. Two four-bedroom units on the higher floors will be released for leasing in the summer, according to the building’s publicist. Some studios are spacious with separate home offices, as zoning regulations mean they are not legal bedrooms. Twenty-five percent of the apartments have been set aside as affordable, and the housing lottery is set to close May 5. Compass Development Marketing Group is handling the leasing.

[NYguy]

https://www.nytimes.com/2025/04/28/business/midtown-development-pfizer-headquarters.html

Apartments for Rent in a Former Office, but You Have to Live in Midtown
The developer behind transforming Pfizer’s former headquarters in Midtown Manhattan into about 1,600 apartments is hoping young people won’t care about the area’s lack of a neighborhood.





By Ellen Rosen
April 28, 2025

For many New Yorkers, Midtown Manhattan, with its gleaming skyscrapers and busy transportation hubs, lacks an element of cool and cachet that its more culturally vibrant neighbors have. Hordes of office workers, commuters and tourists typically flood the area, leaving it feeling anything but residential.

What Midtown does have, though, is a glut of underutilized office buildings. Two in particular brought Nathan Berman, chief executive of Metro Loft Management, to the area: the hulking buildings of Pfizer’s former headquarters on East 42nd Street near Grand Central Terminal. Metro Loft, along with David Werner Real Estate, is converting the buildings into about 1,600 rental apartments.

Once completed, the project would be the largest office-to-apartment conversion nationwide, Mr. Berman said. The first tenants are expected to move in at the end of next year.

The developers also recently bought an office building around the corner from the Pfizer site to create roughly 450 residences, 25 percent of which will be affordable housing.

Mr. Berman has spent over two decades converting office buildings in the financial district, but the Pfizer project is his first in Midtown. He believes that future tenants, whom he calls “active younger professionals,” will forgo more traditional neighborhoods like Greenwich Village, Chelsea or the Upper East Side, with their charming cafes and green spaces, for splashy building amenities like a gym, a rooftop pool, lounges, co-working spaces, and a washer and dryer in each apartment.

“No one even needs a grocery store anymore, since everything gets delivered,” Mr. Berman said.

Buildings that are converted are usually gutted and reimagined. The old Pfizer buildings have floors that are roughly 200 feet deep, and Mr. Berman will have to divide the space to meet light and air regulations, such as the requirement that each apartment has a minimum distance between an operable window and building walls.

Mr. Berman has had experience doing this. Most recently, he did it at 25 Water Street in New York’s financial district, which had a depth almost as large as Pfizer’s old offices. The solution: Create two atriums so that more windows can be added to apartments. The plan is to do the same at the Pfizer buildings.

As for whether young people will happily move to the bustle of Midtown: If the past is any indication, it’s possible. It happened in both the financial district and Hudson Yards, the mixed-use area on the western edge of Manhattan where Pfizer has relocated. Mr. Berman hopes to replicate the success in Midtown.

He said, “Shaking and transforming buildings in the middle of what is an office area takes an empty office building off the market and brings in residential and that will invigorate an area.”

[NYguy]

https://www.bloomberg.com/news/articles/...r-residential-conversion?srnd=phx-latest

Wall Street Tower Seeks $850 Million for Residential Conversion

By Patrick Clark
May 30, 2025

Developers are seeking a construction loan of about $850 million to convert Manhattan’s 111 Wall St. into more than 1,500 apartments in what would be one of the largest office-to-residential projects in the city’s history.

InterVest Capital Partners is working with advisers from Walker & Dunlop New York Capital Markets to line up financing for the transformation, people familiar with the process said. The loan would represent about 65% of the total project costs and allow for the addition of five stories to the existing building, according to one of the people, who asked not to be named discussing the financing process.

InterVest plans to work with Nathan Berman’s Metro Loft, which specializes in office-to-housing conversions. An InterVest representative didn’t immediately respond to a request for comment. Representatives for Walker & Dunlop and Metro Loft declined to comment.

Plans for 111 Wall St. include luxury amenities such as a spa, a bowling alley and a rooftop swimming pool. About 25% of the units will be reserved for renters earning 80% or less of the area median income, allowing the project to qualify for a tax-abatement program, one of the people said.
The loan would be larger than the $720 million Madison Realty Capital originated for the residential conversion of Pfizer Inc.’s former headquarters in Midtown.

https://commercialobserver.com/2025/05/5-times-square-conversion-housing/

State Gives Green Light for 5 Times Square Conversion Into 1,250 Units


By Isabelle Durso
May 22, 2025

A state agency has given the green light for a major office-to-residential conversion in Times Square.

The Empire State Development (ESD) board of directors, which runs the state’s economic development corporation, voted Thursday to allow the transformation of the 38-story office tower at 5 Times Square into a mixed-use development with as many as 1,250 housing units, 313 of which will be permanently affordable. There will also be more than 37,000 square feet of retail space, according to an announcement.

The confirmation of the project comes after Apollo Global Management, SL Green Realty and RXR — which co-own the property through a long-term leasehold with the city — filed plans in December to convert the 1.1 million-square-foot office building into a residential and commercial property with a new address of 592 Seventh Avenue, as Commercial Observer previously reported.

In addition to residential floors, the developers’ plans included coworking spaces, a party room, tenant recreation rooms and storage units, CO reported.

The ESD’s Thursday vote also approved an amendment to the 42nd Street Development Project — the three-decade-long push from the city to revitalize a 13-acre section of the neighborhood which wrapped up in 2010 — that will enable the conversion of 5 Times Square, which currently sits at 77 percent vacant, the announcement said.

Construction on 5 Times Square — which is expected to create approximately 1,400 construction jobs and 830 permanent direct and indirect jobs — is set to begin during the third quarter of 2025, with the first phase anticipated to be completed in 2027, according to the announcement.

[NYguy]

So many conversions, I’m already way behind.



https://www.multihousingnews.com/tf-cornerstone-to-convert-manhattan-tower-into-multifamily/

TF Cornerstone to Convert Manhattan Tower to Multifamily





By Claudiu Tiganescu
August 6, 2025

TF Cornerstone will convert Tower 57, a 397,354-square-foot office tower in Manhattan, into a 350-unit multifamily property. Completion is slated for 2028, Commercial Observer reported.

The company will utilize New York’s 467-m program, which provides a partial tax exemption, and in return, 25 percent of the units will be reserved for future residents earning up to 80 percent of the area median income.

To kick off the project, TF Cornerstone signed a ground lease with the Wallace family. Cohen Brothers Realty previously held that contract; however, its plans for residential adaptive reuse had been rejected by the Wallaces, which then took control of the property last October.

Located at 135 E. 57th St., the 1988-built office property rises 32 stories in Manhattan’s Billionaires’ Row, within walking distance of Grand Central and Central Park.

The building features floorplates ranging between 5,700 and 14,000 square feet. Additionally, Tower 57’s architectural design, including 12-foot ceilings and floor-to-ceiling windows, helps solve the problem of dark interiors common in office-to-residential conversions.

Manhattan’s office-to-multifamily pipeline grew 59 percent year-over-year as of February, reaching 8,310 units under construction, the same source shows. These projects are propelled by incentives such as the City of Yes and the 467-m tax bill.

Metro Loft Developers and David Werner Real Estate Investments are behind one such development, reimagining Pfizer’s former headquarters into a 1,602-unit community. Upon completion, it will be the biggest conversion project in the nation.

Last December, TF Cornerstone forged a $1 billion joint venture with Dune Real Estate Partners. The partnership targets conversion projects outside of Manhattan as well.

https://x.com/EARTH_96283/status/1480979353878122497

[NYguy]

Another nearby candidate…


https://therealdeal.com/new-york/2025/08/07/vornado-realty-trust-to-sell-150-east-58th-street/

Vornado eyes $250M+ for NYC’s designer Mecca
REIT puts Architects & Designers Building at 150 East 58th Street up for sale


By Rich Bockmann
August 7, 2025

Steve Roth’s REIT has put the Architects & Designers Building on East 58th Street up for sale, eyeing a price north of $250 million, The Real Deal has learned.

The 550,000-square-foot building at 150 East 58th Street is “an ideal candidate for a residential conversion or an office rebranding initiative,” according to a marketing memo from Eastdil Secured, where a team led by Gary Phillips and Will Silverman is handling the sale process.

With more than 200,000 square feet of showroom space, the A&D Building is currently a Mecca for designers in the city who can shop for brands like B&B Italia and Sub Zero/Wolf Appliances in one building. It also has more than 300,000 square feet of offices.

[NYguy]

I'm interested in what extent they will alter Tower 57. It's a cool focal point of this stretch of 57th...


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And just around the corner, 150 E 58th. Years ago, I worked at the Alexander's department store (not sure how many on this site can remember that store), before it became the Bloomberg Tower. The Alexanders name still lives on in real estate, Vornado is still a part of it. But the employee entrance faced this tower, and I never really thought much about it. However, it could go either way, as a residential conversion, or a complete teardown and rebuild as a completely new and taller residential building. That will all depend on who the buyer is.



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Aerial view shows the proximity of both towers in their surroundings...


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[NYguy]

Meanwhile, even some of the newer towers are feeling the conversion heat...


https://www.bisnow.com/new-york/news/off...to-undergo-residential-conversion-130498

Capstone, BH3 Foreclose On New Office Tower In Downtown Brooklyn, Plan Residential





August 08, 2025
Sasha Jones

A joint venture between BH3 Management and Capstone Equities acquired the 141 Willoughby St. building via foreclosure, according to deed records filed this week. The group now plans to reposition the 24-story tower into 200 apartments and 110K SF of commercial space.

Manhattan-based Savanna developed the 400K SF office tower on a speculative basis and delivered it in 2023 but never managed to attract a tenant. Only the second through seventh floors are set to remain as office space under the new plans.

“141 Willoughby Street presents a truly unique blank slate upon which to reimagine a newly developed institutional-grade asset,” BH3 principal and co-Portfolio Manager Adam Falk said in a statement.

Office and retail leasing at 141 Willoughby is still underway, while the residential conversion is set to begin next year. The units will be a mix of market-rate and affordable housing with studio, one-, two- and three-bedroom layouts.

In a statement, Capstone partner Avi Kollenscher said the redevelopment will “unlock the full potential” of the building.

“This is a rare opportunity to deliver a mixed-use product that aligns with how New Yorkers live and work today,” Kollenscher said.

[Busy Bee]

Even though I have no memory of or personal connection to it, I have a strange sense of nostalgia for Alexander's:


___

[NYguy]

Originally Posted by Busy Bee

Even though I have no memory of or personal connection to it, I have a strange sense of nostalgia for Alexander's:

I still have a shopping bag from there. So many stores in NY have closed over the years, and exists only as memories.



https://www.flickr.com/photos/26816223@N07/8372725456

[NYguy]

https://www.crainsnewyork.com/real-estat...residential-conversion-midtown-manhattan

Rudin planning office-to-resi conversion on Third Avenue





Julianne Cuba
September 16, 2025

A major real estate player is looking to convert a Midtown office tower into a residential building with more than 400 apartments, records show.

Rudin submitted plans to the Department of Buildings this week to convert the 21-story office building at 845 Third Ave. into 411 dwelling units across 308,114 square feet of residential space with 9,103 of commercial space on the ground floor. The approximate job cost would be $41.7 million, according to the filing from company Vice President Paul Mandel, although the final price tag is often significantly higher than the estimated amount.

Located between East 51st and East 52nd streets, the existing office tower appears to be fully leased, according to information from CoStar. Its tenants include several law firms, the South African consulate general and media company Vector Media, according to CoStar.

At least one of the building's tenants, however, already has plans to relocate, likely in anticipation of the conversion.

The proposed conversion to residential would include a number of luxury amenities within the building, such as a lounge, a party and media room, and a spa area with saunas, a plunge pool and a Zen garden, all on the cellar level. It would also have a fitness center and coworking space. The upper floors of the building, meanwhile, would include private terraces for certain apartments, bicycle storage and another pool and lounge on the roof, records show.

[NYguy]

https://www.crainsnewyork.com/real-estate/tower-57s-saks-fifth-store-close-december-lay-workers

Tower 57’s Saks Off Fifth store to close in December as building's conversion looms





C. J. Hughes
September 23, 2025

The Midtown high-rise at 135 E. 57th St., which developer TF Cornerstone took over last month to embark on a major office-to-residential conversion, is losing a retail tenant, discount department store Saks Off Fifth.

The closure, which will result in the loss of jobs for all 33 of the store’s workers, is happening in order to avoid the imminent three-year-long construction process that will create 350 rental units at the 32-story high-rise at Lexington Avenue, a spokesperson said.

The conversion, which is set to start in the summer and wrap up in 2029, will also eliminate the building’s retail spaces, so the store’s home would be going away anyway, they added, though a TF Cornerstone spokeswoman did not confirm that detail by press time.

A Class A mainstay of Midtown East since it was completed in 1988 and enough of a fixture of the skyline that it was used in 2002’s Spider-Man movie as the corporate HQ for Green Goblin alter-ego Norman Osborn, Tower 57 has been barely more than half-leased in recent months, as Cohen apparently struggled with the site’s debt load.

Of the 350 rental units that TF Cornerstone plans to carve out of the 456,000-square-foot building, about 25% would be set aside as affordable at 80% of the area’s median income, or $116,640 for a family of three, TF Cornerstone executives have said.

[NYguy]

https://www.crainsnewyork.com/real-estat...ington-ave-office-residential-conversion

Rudin plans another Midtown office-to-resi conversion





Eddie Small
September 29, 2025

Rudin is adding an additional office-to-residential conversion in Midtown to its development portfolio.

The family-led real estate firm intends to convert its office tower at 355 Lexington Ave. into a 297-unit residential building, according to plans it recently filed with the Department of Buildings. The height of the tower, located between East 40th and East 41st streets and also addressed as 133 E. 40th St., would increase slightly, rising from 22 stories and 241 feet to 26 stories and 278 feet, and it would span about 280,000 square feet overall with retail space on the ground floor, the filing says.

This is at least the second major Midtown office-to-residential conversion Rudin has moved forward with in recent weeks. The company also filed plans earlier in September to convert its office building at 845 Third Ave., between East 51st and 52nd streets, into a 411-unit residential building.

The projects will include market rate and affordable apartments and help meet the city's strong need for additional housing, a spokeswoman for Rudin said.

[NYguy]

https://therealdeal.com/new-york/2025/09/30/vanbarton-office-to-resi-midtown-conversion-brookfield/

Vanbarton seals latest office-to-resi play with Brookfield loan
Canadian firm provides $300M for 6 East 43rd Street





By Elizabeth Cryan
September 30, 2025

Vanbarton Group locked in a large loan from Brookfield to close a Midtown office deal, marking the developer’s latest office-to-residential play.

Brookfield provided a $300 million loan to finance Vanbarton’s $135 million purchase of 6 East 43rd Street from the Milstein family’s Emigrant Savings Bank. The loan will also be used for Vanbarton’s conversion of the 400,000-square-foot building to 441 rental apartments, including 111 affordable units.

Vanbarton will take advantage of a tax break ushered in by Gov. Kathy Hochul, known as 467m. Developers who set aside 25 percent of a conversion’s units as affordable to those making 80 percent of the area median income can nab a 90 percent off coupon on property taxes under the abatement.

The conversion of the 1968 building is possible thanks to last year’s City of Yes for Housing Opportunity. Before the City Council approved Mayor Eric Adams’ signature housing policy, buildings constructed after 1961, apart from those in Lower Manhattan, were ineligible for conversion. Now, anything that went up before 1991 is fair game.

[NYguy]

This is the last property on the block that isn't becoming a residential conversion - at least not yet...


https://therealdeal.com/new-york/2025/09/30/durst-in-line-to-sell-midtown-east-property-for-165m/

Durst in line to sell Midtown East property for $165M
601W Companies in contract to purchase 205 East 42nd Street





Sep 30, 2025
Holden Walter-Warner

The Durst Organization is on the verge of selling a legacy building in Midtown East.

Durst is in contract to sell 205 East 42nd Street to New York-based 601W Companies for $165 million, according to investor materials viewed by The Promote. Family patriarch Joseph Durst purchased the building for his burgeoning real estate empire more than 80 years ago. The 532,000-square-foot, 21-story property was developed in 1927 and designed by Starrett & Van Vleck.

At the contracted price, the sale would break down to $310 per square foot. Major tenants at the building include the City University of New York, Fedcap Rehabilitation Services and the United Way of New York City. A WeWork formerly operated there, though another co-working company moved into 41,000 square feet of space two years ago, according to the New York Business Journal.

[NYguy]

https://www.bloomberg.com/graphics/2025-nyc-midtown-office-conversions/

A Wave of New Apartment Buildings Are Set to Take Over Midtown Manhattan












By Natalie Wong, Rachael Dottle and Marie Patino
October 6, 2025

[NYguy]

https://www.6sqft.com/midtown-south-office-tower-become-studio-apartments-under-rezoning/

Midtown office tower to become 107 studio apartments, first major conversion under rezoning





By Devin Gannon
October 8, 2025

An underutilized Midtown office building is set to become over 100 studio apartments in its next life. Infinite Global Real Estate and Buttonwood Development, in partnership with 400 Capital Management, have acquired 29 West 35th Street, with plans to turn the 12-story tower into a rental building. The project marks the first major office-to-residential conversion in the neighborhood following the Midtown South rezoning, approved by the City Council this summer.

The developers plan to turn the century-old building into 107 studio apartments, with 27 designated affordable via the 467-m tax abatement program. The affordable apartments will be priced at $1,701/month, with market-rate units closer to $4,000/month, according to Bloomberg.

The units will measure between 400 and 575 square feet and include ceilings of 11 to 14 feet, designer kitchens, and in-unit washer/dryers. A majority of the units will include flexible spaces, like home offices, alcoves, or bonus rooms, to address “the evolving needs of remote work and modern living.”

Amenities will include a rooftop space with views of the Empire State Building, an outdoor movie screen, a doorman, a pet wash station, and storage.

The project will repurpose the existing building, which has been mostly vacant. The bar Liberty NYC currently operates on the ground level. Colliers, led by Zach Redding, Dylan Kane, and Matt Mastrocola of the New York Capital Markets group, arranged the sale.

“New York City is home to some of the world’s most beautiful and iconic structures, many of which have outlived their original commercial purpose but possess incredible architectural character that deserves preservation,” Marty Burger, founder and CEO of Infinite Global Real Estate Partners, said.

“Rather than tearing these buildings down, we have an incredible opportunity to breathe new life into them as homes for New Yorkers.”

“Work patterns have shifted, and proximity to the office is now a top priority for Manhattan residents,” Heiberger said. “They seek efficiency, the ability to walk to work, to enjoy amazing restaurants, and to live in thoughtfully designed spaces. We’re delivering on that vision with 29 West 35th Street, where true live-work lifestyle isn’t a luxury but a priority.”

In August, the City Council voted to approve the Midtown South Mixed-Use Plan (MSMX), which covers about 42 blocks between West 23rd Street and West 40th Street, and between 5th Avenue and 8th Avenue. Updating the zoning rules allows for new housing to be built in the area, which has largely been limited to commercial space. Officials estimate 9,500 new apartments could be built in the neighborhood.

https://nypost.com/2025/10/08/business/c...rime-office-space-turns-into-apartments/

Conversion mania grips Manhattan as more prime office space turns into apartments





By Steve Cuozzo
Oct. 8, 2025

Last year saw twice as much Manhattan office space start to be converted into apartments as the year before – a boom that’s poised to change the chemistry of Midtown neighborhoods historically dominated by office towers, hotels and entertainment venues.

Among them: at least four buildings on Third Avenue in the East 40s and 50s and 135 E. 57th St. at Lexington Avenue, once a symbol of the late-1980s office-development craze. The conversions will bring 24/7 energy and domestic warmth to blocks that are typically quiet after dark.

On the other hand, RXR’s conversion of 5 Times Square into 1,250 apartments — which was one of the quartet of West 42nd Street towers that proclaimed a new era for the “Crossroads of the World” — might have a calming effect on the frenetic street scene around it.

The transformations address two simultaneous crises — the city’s well-known rental housing shortage and the galloping obsolescence of many older office buildings.

Cushman senior research manager Reed Hatcher told the Commercial Observer that “policy support” was helping to accelerate conversions — namely, rezonings by the city to make conversions possible where they weren’t previously allowed, along with state-approved tax incentives to sweeten the deals for developers.

The rezoning of Midtown South, passed last summer, quickly brought results. A partnership just bought 12-story 29 W. 35th St. with plans to create 100 studio apartments.

Conversion mania contributed to a drop in Manhattan’s office inventory from 466.1 million square feet in the second quarter of this year to 449.4 million square feet in the third quarter, according to Savills.

Most conversions before 2020 were in Lower Manhattan, especially in older buildings in the Wall Street area. The phenomenon continued recently at 25 Water St., where tenants are moving into 1,230 rental units.

Now the wave is swamping Midtown, including the former Pfizer headquarters at Third Avenue and East 42nd Street. The project by MetroLoft Developers and David Werner Real Estate Investors will yield 1,602 new rental homes — the largest such project in the US. As The Post reported, it will boast 100,000 square feet in tenant amenities including a rooftop pool.

SL Green is carving over 600 rental units out of 750 Third Ave., where 13 floors are being chopped out on one side to create a winter garden. Meanwhile, Vanbarton group just nailed down a $300 million loan from Brookfield to purchase the vacant office building at 6 E. 43rd St. near Grand Central Terminal and convert it to 441 rental units.

Buildings Department filings showed that nearby, Rudin plans major East Side conversions at 845 Third Ave. and 355 Lexington Ave.