A developer in the new Sixers arena is building 136 apartments and new office space in West Philly

The West Philadelphia development boom continues with a 136-unit residential building proposed at 41st and Walnut Streets, as part of a new corporate headquarters for the Philly-based national student housing company, Campus Apartments.

The company’s CEO is David Adelman, one of the central figures behind the proposed Philadelphia 76ers arena near Chinatown. As Campus Apartments expanded its services to 18 states since 2000, their office footprint in University City sprawled across four buildings.

Now, Adelman plans to bring them all together under one roof, where offices will share space with the residential units that the company is known for.

“There were some people saying, hey, should we move to the suburbs,” Adelman said. “I personally was not going to let that happen. But we wanted to evaluate all of our options as we consolidate our headquarters.”

The new building will require leveling two historic residential buildings, which Campus Apartments already owns, at 4040 and 4042 Walnut St. One is a fraternity house and the other is a small apartment building, with a total of 57 beds between them. Neither is listed on the local historic register, which would provide them protection against demolition.

The new building will contain about 30,000 square feet of office space and retail space for a coffee shop or lunch counter. Amenities will include fitness facilities and shared study areas.

Adelman says they haven’t yet determined the breakdown of living spaces in the building, but it will include a diversity of studios, one-, two-, and three-bedroom units.Adelman expects units to have the same number of bathrooms as bedrooms, since many renters want privacy.

The proposed building is part of a residential boom in University City over the last few years, as multifamily buildings are being planned around the University of Pennsylvania and Drexel University.

“We keep asking where are the bodies going to come from to fill these places,” said Barry Grossbach, chair of the Spruce Hill Community Association’s zoning committee. “Evidently, some of the traditional housing units out here are not filling up like they used to. Students are no longer interested in living with 10 other people in a house with two bathrooms.”

Due to the land’s current zoning classification, Campus Apartments can proceed without any zoning relief. It will clock in at about 162,000 square feet of space and be 10 or 11 stories.

The project won’t use any of the city’s zoning bonuses, which offer greater height or density in exchange for public goods like affordable housing or open space. Adelman says that the proposed buildings border townhouses to the immediate south and he doesn’t want to overwhelm them.

“We don’t want something too massive here because we’re adjacent to the community,” he said.

An earlier proposal for this development would have required the demolition of homes on the so-called Beige Block, a cluster of historic townhomes — all owned by Campus Apartments — that largely serve as student housing. But the homes directly to the south of Walnut Street are zoned for lower density residential use, and the company would have had to seek an exception at the Zoning Board of Adjustment and expected to face backlash from community groups.

“We are very much opposed to demolishing houses out here,” Grossbach said. “They sensed that we were not amenable to a zoning change and they decided that they would build along Walnut Street instead.”

Campus Apartments also filed the permits for their new headquarters before Councilmember Jamie Gauthier’s mandatory inclusionary zoning law went into effect throughout much of University City. The law requires any residential project of 10 or more units to price 20% of the available spaces below market rate to ensure available housing for people with lower incomes.

Adelman said the project had been considered for years before permits were filed and the timing is a coincidence.

“We have been contemplating this project for the last five or six years, doing our due diligence on where to move the office,” Adelman said. “And we finally did it. So the timing just was what it was.”