Inside the $500M+ Renovation That Transformed an Iconic Skyscraper into a Mixed-Use Destination

When Chicago’s Sears Tower opened in the 1970s, it anchored the Windy City’s world-class skyline. At 1,450 feet and 108 stories tall, it was once the tallest building in the world, holding that distinction for 25 years.

While the architectural icon was impressive for its vertical construction, the experience inside the building didn’t rise to meet the needs of its 15,000 office workers or 1.6 million annual visitors to the Willis Tower Skydeck. And, it certainly wasn’t drawing in the 170,000 Chicagoans who work within a five-minute walk of the skyscraper to come visit.

Willis Tower’s lobby, trafficked by its thousands of tenants per day, wasn’t being used thoughtfully, idling as untapped, dead space that EQ Office, the Blackstone-owned real estate portfolio that purchased the tower in 2015, wanted to activate.

“We needed to take a fresh look not just at the building, but at the experience in it,” described Michael Townsend, design director and leader of mixed-use and retail centers at Gensler, the architecture firm that led the project. “We asked, ‘What are the things that could help improve the experience of all three of [the building’s] user groups?’”

The answer: retail, food and beverage offerings. “That was something that was missing sorely from Willis Tower itself, but also from that part of the Loop neighborhood too,” Townsend explained, referring to the central portion of Chicago’s downtown that takes its name from the circular elevated track that trains ride around the neighborhood.

The designers took what they described as a “confusing fortress” of the Willis Tower lobby, and through a renovation totaling more than $500 million created 300,000 square feet of retail and dining space known as Catalog, a nod to the building’s former trademark as the Sears Tower (the insurance brokerage now known as Willis Towers Watson acquired the building’s naming rights in 2009). The Catalog is a four-story “podium” addition, or mezzanine-style structure that wraps retail and lounge space around a central, light-filled atrium.

The project also included a new 30,000-square-foot outdoor terrace that’s accessible to the public and 150,000 square feet of new tenant-exclusive amenity spaces.

“The building is an amazing landmark, but our goal was to figure out how to bring meaningful programming to the podium level,” said Hansoo Kim, design director and interior design principal at Gensler. “Not just for the office tenants and tourists, but for Chicagoans — we wanted to bring the soul and style of Chicago inside this space.”

1.6 million people take in the panoramic views from the Skydeck of Willis Tower each year, yet until recently had no other reason to be in the building as a visitor. Add that to the fact that the building’s different users — office workers and tourists — had isolated entrances on different blocks, leading into a stark and empty marble lobby, and it made the overall experience less than inviting.

“It felt very fortress-like, and as a visitor to the Skydeck, you had no idea where to go — there were no signs to direct you to the top of the building, and you had to first take an elevator to the basement before making your way to the top,” described Townsend. “It was very one dimensional in terms of what you did there — the totality of your experience as a visitor to the building was confusion, and you didn’t actually see Willis Tower in any meaningful way.”

Taking up a full city block, the building’s previously disconnected entrances today lead visitors into the central retail atrium, a public, four-story mezzanine that circulates around lounge and eating space. An expansive 75-by-85-foot glass ceiling over the atrium fills the space with natural light and allows entrants to gaze up at the iconic tower from the base of the building.

Imbuing the Catalog with the essence of the city to emulate the “vibrant streetscape of Chicago,” retail tenants at Willis Tower showcase a mix of Chicago-born local eateries, such as Rick Bayless’ Tortazo, Lettuce Entertain You’s Sushi-san, Do-Rite Donuts & Chicken, Brown Bag Seafood Co., full service restaurant Kindling, a new char-house style restaurant from Chicago’s Fifty/50 Group which opened this month, and corner store café market Foxtrot are all part of the new food hall.

The renovation also added a newly-built 30,000-square-foot outdoor terrace that’s accessible to the public, bringing much-needed green space to Willis Tower’s corner of the Chicago Loop, explained Townsend. Art installations, both inside and on the exterior of the building, including one by Jacob Hashimoto, a graduate of the School of the Art Institute of Chicago, activate the streetscape and showcase the work of local artists.

Tenants are responding to the new and improved building, which now offers more than just its prestigious address. In addition to the Catalog and green space, the tower features 150,000 square feet of new tenant-exclusive amenity spaces including cafes, bars, meeting spaces and a fitness center.

“Almost immediately following the completion of the first phases of the redevelopment, leasing activity picked up and it has not slowed since,” Kirsten Ekdahl Hull, vice president of portfolio management for building operator EQ Office, told LoopNet in an email. “Since starting the redevelopment, we have welcomed many new customers to the building including National Restaurant Association, Morgan Stanley, GATX and Abbott.”

A big win for the tower was securing a lease renewal with United Airlines, one of the largest tenants in the Chicago market.

“[United] would have been the ideal anchor tenant for several new development sites around Chicago. United not only required a highly-amenitized building, but was also looking to reset its work environment with fresh new space,” said Hull. “Therefore, the decision to renew at Willis Tower required a comprehensive plan for reconstructing and restacking.”

The company occupies over 800,000 square feet in the building. United’s new renovated office space includes a 35,000-square-foot private amenity floor equipped with café spaces, food service, conferencing, coworking, social spaces, town hall meeting areas, and two private outdoor spaces.

According to CoStar, the publisher of LoopNet, the 4 million-square-foot building is 89% leased, up from 80% prior to the redevelopment.

With the fate of many office buildings at a crossroads in the wake of the pandemic, repositioning assets to meet the demand of today’s tenants may well separate the buildings that remain leased from those that become obsolete.

For Willis Tower owners EQ Office, this meant focusing on amenities that pull employees back to work by fostering collaboration, camaraderie and a sense of community to build a dynamic work culture.

“When EQ Office sets out to reposition a property, our entire focus is on driving humanity and authenticity into the workplace,” Hull said. “The transformation has resulted in a human-focused, hospitality-driven, amenity-rich environment that people will choose to come to even if they have the ability to work from home.”

While Gensler’s Townsend joked that he might be biased as the firm’s mixed-use practice leader, he said the project underscores the power of mixed-used properties in keeping buildings relevant.

“Everyone is trying to figure out what the next generation of downtown cores and buildings in central business districts is. This is a great example of how we can take a building that’s 50 years old and extend the life of it for the next 50 years. What do the next 50 years of Willis Tower look like?” he said.

That future is mixed-use, he continued. “Mixed-use adds complexity [to a project], but I think what's exciting about our cities is the juxtaposition of these [elements] and their being better because they're co-located,” he said. “With that, there is the expectation that it will drive footfall because people want to be there — it’s a more interesting and energetic place to be because it provides all these options.”

As arguably one of the world’s most iconic buildings, the new renovation brings modernity to the tower while celebrating its past. For the designers, updating the landmark meant that any design choices should first and foremost honor the existing tower, evoking the sense of stature and prominence it holds for Chicago residents and many nonresidents as well.

“This building has such brand recognition, and people have experienced it for generations. It has one foot in the past, but it also has aspirations towards the future — what the future of work could be, and what the future of our cities is,” Townsend said.

The color palate and materials speak to the tower’s existing character, with strong dark black framing that contrasts with sleek metal and glass.

Even in an architecturally stately space, the designers balanced the striking materials with warmth, incorporating white terracotta, a material that is used across historic buildings in Chicago’s Loop, in the entryways.

Kim explained that even though the design team built out the retail floor as a new architectural interior, “it doesn’t feel that way. We were very sensitive as to how we could inherit the material of the old building, so it feels very blended and harmonized with the existing tower.”

“We started to layer on materials and texture that were purposeful to help humanize the space a bit,” added Townsend. “Willis Tower was built as a monolithic structure that wasn't particularly friendly at the ground, and it can be a pretty stark building. So we had to add a little bit of an extra layer of depth, detail and texture, plus a few new materials to help make this a more hospitable place for people.”

The interior design was also driven by hospitality spaces, a trend that Townsend said has been infusing workplace design since well before COVID-19.

The inviting lounge spaces blur the lines between uses, from work to leisure, to create an amenity-rich environment for its tenants and visitors.

“This is not just about a hospitality ‘look and feel’, but a hospitality experience that provides options, a menu of choices for people,” said Kim. “So maybe a group is sitting at a communal table in the office lobby, or on a bench-style seat to eat lunch on the retail podium. The furniture is inclusive and universal, since you have several generations using the space — from baby boomers to Generation Z. The diversified and inclusive design supports an equitable and hospitable experience.”

Noting that the role of the office and the way tenants work began to evolve before the pandemic, Hull emphasized that having “a dynamic, activated lobby space helps tenants feel welcomed and energized when they head into the office. The physical office used to be a place where people had to come to work ... now it needs to be a place where people want to come to work. The shift in energy we have seen in Willis Tower since we completed the transformation has been very positive and encouraging.”