Walking into the atrium of Rush University Medical Center’s new building, the glistening wide-open space isn’t like many other hospital lobbies.

Filled with natural light and few physical obstructions, the Edward A. Brennan Entry Pavilion is more akin to an enclosed public square. The lone feature in the middle of the room is a wide glass tube extending down from the ceiling that encloses trees and soil — a continuation of the green roof atop the atrium.

But like many features of Rush’s brand new structure, beneath the beauty is a practical use. Hidden inside panels on each of the pillars along the outside of the pavilion are connections to oxygen, electricity and other medical essentials, allowing the pavilion to become an expanded emergency room in case of a major catastrophe.

Designed by the architecture firm Perkins+Will, the 14-story new hospital building at 1620 W. Harrison St. has loomed over the Near West Side and the Eisenhower Expressway, evolving for several years now, and it’s expected to finally open on Jan. 9.

In advance of the opening, Chicago Journal was invited to take a tour of the new facility this week. The hospital will offer tours to the general public on Dec. 10 to community members who RSVP.

The new building arose not just from want but from need, according to Dr. Anthony Perry, clinical officer of the Rush Transformation team. A geriatrician, he was part of the small group tapped to lead the charge toward the new building, which came out of a strategic plan, calling for Rush to recommit to its campus in the Illinois Medical District, Perry said.

“As we looked at it, we were operating in facilities that were pretty tired overall. I mean, we literally had patient care facilities that dated back to the end of the 1800s,” he said. “To us, there was really an imperative. Building this building really wasn’t an elective; we really had to build it to change our campus.”

The new structure definitely accomplishes that architecturally, starting with the distinctive butterfly-shaped floors atop the new building’s base. The goal was to give each room the maximum amount of light while keeping their size and shape consistently the same. To do that, Perkins+Will took straight walls and pinched them in, thus creating pods with straight hallways, patient rooms on the outside and staff rooms on the inside.

The new patient rooms are identical on the top floors, Perry said, making it easier for medical teams to work quickly in an unfamiliar room in the event of an emergency. By not having to think about where the oxygen connections are, for example, response time should be much quicker — a potential life saver.

On the first floor, the emergency room is part of a brand new bioterrorism and major disaster response plan for Chicago, paid for by a $7.5 million grant from the McCormick Foundation and major grants from the federal government.

On top of the ability to expand the ER into the Brennan Pavilion, each of the rooms has the ability to change its air pressure on demand to match each patient’s situation. Individual rooms can be negatively pressurized so contaminated air from dangerously contagious patients never leaves the room, and is immediately sucked out, filtered, and expelled from the building.

The ER’s loading bay, where ambulances drop patients off, can be closed off and turned into an expanded decontamination zone for victims of a chemical or nuclear attack with showers that drop from the ceiling.

It’s an all-around major upgrade from Rush’s current emergency room, which is in one of the campus’ older buildings, set to be demolished soon after the new building opens, Perry said.

The new facility displaced a small outdoor space with tennis courts and a plaza for patients, and Rush is planning to tear down four older buildings on the edge of their campus to replace that green space, Perry said. The structures being razed — the Murdock, Senn, Rawson and Jones buildings — will mostly have their functions replaced in the new hospital building or moved to other, better maintained buildings throughout the campus.

Jonathan Fine, president of Preservation Chicago, said that while his group isn’t particularly pleased that the buildings being demolished, they weren’t worth a fight at this point.

“Unfortunately, they had been remuddled over the years,” Fine said. “They started out as very nice Victorian buildings. We were aware that Rush wanted those buildings down when we were fighting the Cook County Hospital fight, but at that point we sort of picked our battles.”

One aspect of the new Rush building warms his preservationists’ heart though: He sees this building as an homage to another hospital building he’s fighting to save across town — Streeterville’s Prentice Women’s Hospital.

Anyone interested in a tour of the new Rush Hospital between 9 a.m. and 5 p.m. on Dec. 10 should sign up by calling 888-352-RUSH (7874) to reserve a spot.