An office-to-apartment conversion is underway in Logan Square. Here’s why it works.

The residential conversion of the former office building at 2100 Arch St. is underway, with completion expected in late 2027 or early 2028.

Philadelphia-based MM Partners paid $12 million for the eight-story building in March 2023, with plans for 116 apartments in the Logan Square neighborhood.

It was formerly the Jewish Community Services Building.

But the site was quiet for a few years and the project delayed by skittish lenders who were concerned about financing more apartments in a market they saw being flooded with new supply. Construction finally began in July.

“It wasn’t easy, but we just stuck with it and figured out a way to get it under construction,” said David Waxman, founder and managing partner with MM Partners.

“The good part of [the delay] is we’ll now be delivering into a market with very little new supply, particularly in this part of the city,” he said.

The project will be composed of studios, with the smallest in the 500-square-foot range, up to two-bedrooms that will be up to 1,400 square feet. There will be 36 studio apartments, 64 one-bedrooms, and 16 two-bedrooms.

MM Partners is planning 3,000 feet in commercial space on the ground floor of the original 113-year-old building and is considering a roof deck as well.

In the basement, tenant amenities such as a gym and lounge are planned, and MM Partners is considering providing 1,200 square feet of rehearsal space for Philadelphia theater companies.

“There’s a lot of local theater companies that are looking for efficient and affordable space,” said Aaron Smith, partner and founding member with MM Partners.

In many ways, 2100 Arch St. is an ideal office building for residential conversion.

It is relatively small at 121,500 square feet and has none of the cavernous, sunless interior space that makes more recent, skyscraper office buildings so hard to convert.

That means tenants will have access to windows without carving light wells through the center of 2100 Arch. The number of apartments is more modest than would be the case in the large towers on West Market and therefore easier to fill.

“It’s not too big and not too small,” Waxman said. With a lot of large office buildings, “you have to buy it so cheap to be able to afford to just have dead space in the middle.”

MM is working with King of Prussia-based Axis Construction Management on the 2100 Arch conversion. It is their eighth adaptive reuse project together.

For the $26 million project, MM Partners was able to secure $6.1 million in federal historic tax credits and $500,000 from Pennsylvania’s Historic Preservation Tax Credit.

While the original building is over a century old, half of it dates to the 1980s when it was home to BIOSIS, a life sciences database publisher.

The eastern section of the building was constructed in 1913, and then acquired by BIOSIS in 1966. The company grew throughout the later half of the 20th century and doubled the size of the structure to the west in 1982.

Like other conversion projects in Philadelphia, 2100 Arch will get a 10-year property tax abatement.

The developer acquired the building from the Jewish Federation of Greater Philadelphia, which had purchased it from BIOSIS in 1999, after the building had been vacant a short time due to the COVID-19 pandemic.

“They had done a really nice job keeping it up,” Waxman said. “If there had been an office market for B- and C-class buildings, this could have been easily leased as office. But there isn’t. Everyone only wants to be in the nicest buildings now.”

In sharp contrast MM Partners has adapted long-derelict buildings to new uses in other parts of the city, such as the F.A. Poth Brewing Co. in Brewerytown, which MM converted to 133 loft apartments.

Some of those buildings had severe structural problems as a result of their long abandonment, whereas 2100 Arch was in perfectly good shape.

“It’s a joy to work in,” Waxman said. “You have working elevators. You have a non-leaky roof. You have electricity coming in. You have sprinklers. You have all the things that these other buildings that we’ve done in the past didn’t have.”

Meanwhile, the nearby west side of Center City has become the heart of Philadelphia’s commercial life.

West Market Street, visible from 2100 Arch’s south-facing windows, is the most successful corner of the city’s office market.

Insurance giant Chubb’s new office building just opened next door. Burlington recently announced plans to move its headquarters into the Schuylkill Yards development near 30th Street Station.

At 2100 Arch, “you’re close to everything, but you have a little oasis [in the Logan Square neighborhood] right next to the hustle and bustle of Market Street,” Waxman said.