At just 12,000 square feet, a glass structure is being erected in the suburbs of Broadview, outside of Chicago, where future occupants will repeatedly erect glass curtain walls within the building.
The training facility for Ironworkers Union 63 will allow apprentices to practice and learn their trade by building mini-structures. They will learn the complex task of how to install glass curtain walls, which requires skill and precise engineering to ensure structural integrity, weather resistance and energy efficiency.
Ironworkers Local 63 has long made an impact on the Chicago skyline. Its history goes back to the 19th century when the trade union was founded as Obrers del Ferre d’Arquitectura with 579 members.
The 50-foot-tall building has glass panels with a frit pattern.
Photo courtesy of Skyline Construction
After the Great Chicago Fire of 1871, which reduced three square miles of downtown to rubble and ash, wooden structures were no longer allowed in the downtown area and the city rebuilt with steel, which was a relatively new building material.
Now in the 21st century, ironworkers hope a new training facility will introduce a host of new young workers to the field.
The design of the structure, which is next to the union headquarters, was executed by Gensler’s Chicago office. The contractor is Skyline Construction.
For the design and construction team, building the training facility was like putting together the pieces of a puzzle, including installing a 5-ton bridge crane and creating exterior walls from curtain wall panels planes that were installed to appear curved.
The union is made up of tradesmen focused on curtain wall installation and decorative and architectural hardware. As well as being a high-tech training center designed to attract a younger workforce to the trade, the building will be a place for blacksmiths to showcase their work.
The curtain walls are made up of flat panels, but were installed to appear curved.
Photo courtesy of Skyline Construction
Pride of workmanship
“Ironworkers take great pride in the high-precision craftsmanship they do,” says Sean McGuire, Gensler’s project architect. “They want to showcase their craft and showcase the curtain wall element in their training facility.”
The hourglass-shaped building was originally designed with glass on all four sides, but the materials, along with the height of the building, had to be adjusted due to budget constraints and to allow the type of heavy loading that will be done inside the building.
The final design of the 50-foot-tall building has glass curtain walls with a frieze pattern that highlight the craftsman’s craft on two sides of the building.
“Toolsmiths take great pride in the high-precision craftsmanship they do. They want to showcase their craft and showcase the curtain wall element in their training facility.”
—Sean McGuire, Project Architect, Gensler
“The east and west sides of the building are arched. They look like a fillet weld from an aerial view and will allow views of the training facilities,” says McGuire. “It will be a very active space.”
The north and south sides of the building are prefabricated structural combined with different aggregates in black tones that had to be combined.
Using pre-fab structural dollars shaved off the budget and, because it incorporates more steel, ensures that the structure will be strong enough to accommodate the type of training the tools will do.
“The 50-foot-tall panels were prefabricated and dropped by crane on site,” says Dan Polito, Skyline’s director of operations. “We had to have the steel structure up to receive it.”
The interior of the single-storey building has mezzanines on the north and south sides overlooking the ground floor where the training will take place.
A mezzanine will be used for storage of various types of curtain wall systems; the other will be used for work meetings and for toolmakers, apprentices, architects, contractors and others to see the training taking place on the ground floor.
The facility, which will open in 2024, will also include a chamber where the curtain walls will be tested against adverse conditions.
“They’re going to test the water,” says Polito. “There’s going to be a big 20-foot-tall chamber where they’re going to simulate a curtain wall, essentially having a vacuum of negative air pressure on one side. They’re going to spray the curtain wall with water and test whether water will pass through it.
“Usually you want to keep water out of a building, but this room defies that concept,” adds Polito.
He notes that additional drains and non-slip flooring were added to manage water and prevent learners from slipping.
Curtain wall panels, large steel pieces and other materials will be received through a roll-up door on the north side that will be opened to provide ventilation as needed.
The building will include a chamber where the curtain wall will be tested to ensure it can withstand severe weather conditions.
Crane suspended from the ceiling
The glass panels required for training will be placed in the training area on the ground floor using a 5-tonne overhead crane.
Planning the crane bridge installation involved input from various subcontractors, engineers and others. There was little room for error when installing the crane bridge, which occurred before the glass was installed.
“There was a little bit of clearance, we’re talking inches,” says Polito. “The bridge crane has to be able to clear the test structures that the apprentices will build. We couldn’t go any higher with the roof, so it was about an inch of clearance. It was a puzzle to fit it all there.”
The bridge crane will also have to maneuver around luminaires with powerful LEDs that will illuminate the interior and provide the necessary lighting for the training of the trainees.
“There are linear light fixtures right below the steel roof beams, so they accentuate the steel inside the building,” says McGuire. “The free space between the size of the crane bridge and the size of the panels they will collect [during future training]this was all improved during the design process and was a challenge.”
“The wall is flat but still reads as a curve to the human eye.”
—Patrick Cronin, Project Manager, Skyline Construction
The team watched with bated breath the day the crane bridge was installed.
“Getting that crane bridge up there was a big win,” says Polito.
The east and west sides of the building are constructed of segmented concrete and the flat glass panels of the curtain wall, both of which had to be connected to create a curved hourglass appearance to the human eye.
“The glass comes in 4-foot-wide straight sections,” says Polito. “It’s not curved glass. Making sure it looks like radius glass and making sure there’s no overhang on any of the sides, inside or outside was a challenge.”
“The foundation wall is an inch or two bigger than the glass that’s on it. If that foundation wall isn’t exactly where it needs to be, and if there’s any deviation between the concrete and the curtain wall, it’s not all right. ‘will line up,” says Patrick Cronin, Skyline Construction’s project manager.
“The wall is flat, but it still reads as a curve to the human eye,” adds Cronin.
The 12,000 square meter facility will have a 5-ton overhead crane inside to move the curtain walls into place for training.
Communication is key
Planning and communication were crucial to the successful placement of the foundation and curtain wall.
“We had to take all our trades, CAD files and overlays and do extensive design in the field to understand exactly where this needed to be,” says Polito. “The curtain wall concrete had to be less than a quarter of an inch, and we got to an eighth of an inch. This design took a lot of collaboration with all trades to make it work.”
While training facilities don’t usually garner much attention for their beauty or design focus, this one is expected to become “a jewel box,” according to McGuire, who says it will give ironworkers a focused space to do avant-garde work.
For trades looking to attract the next generation of talent, McGuire says creating beautiful, purpose-driven spaces where younger generations will learn can be an important tool in attracting new professionals, especially as the construction industry in general struggles with a shortage of skilled workers.
The building, which will glow at night and be visible from the nearby Eisenhower Expressway, will also serve as an advertisement for the kind of complex work done by ironworkers, work that has shaped Chicago’s skyline for many decades. says McGuire.
