The Terrace 459 mixed-income development in Chicago is a shining example of how precast, prestressed concrete can help architects solve multiple design, schedule, and budget challenges with a single material.
This new residential building replaces a portion of the infamous Cabrini-Green housing project with a lower-density development featuring a combination of subsidized housing, affordable apartments, and market-rate condos and townhomes. The nine-story, 160,000-ft2 building is part of the Chicago Housing Authority’s (CHA) Plan for Transformation to integrate public housing and its residents into the larger social, economic, and physical fabric of the city. The final design contains 36 units of replacement housing for former Cabrini residents, 27 affordable apartments, and 43 market-rate apartments, along with 66 off-street parking spaces, community spaces, and management offices.
The overarching goal of the project was to create a more economically diverse community to attract residents across broad social and cultural demographics, says Peter Landon of Landon Bone Baker Architects. But delivering such a structure within tight budget constraints and multiple funding requirements wasn’t easy.
At the outset of the project, Landon’s team wasn’t even considering precast concrete as a design option. However, the desire for an economical system that could bring scale and design options to the building quickly led them in that direction. “Precast concrete reduced the cost of construction,” Landon says. “The economy of scale and speed of construction freed the project to produce market-quality units on a tight budget.”
The team achieved further structural benefits by designing a precast concrete floor and wall system that delivers an integral structure and skin, a tight envelope, and cost-effective fabrication and assembly system.
Though precast concrete offered more than form and efficiency, Landon says. The close collaboration between his team, the precaster and contractor allowed them to push the design potential to achieve many benefits from the precast design.
The precast concrete design resulted in a modern and inviting structure with lots appealing details, including brightly colored balconies, sunny courtyards, and a varied façade that lightens the bulk of the building. “The pedestal base of early schemes eventually gives way to panels that come down to grade and connect the apartments to the street,” he explains. “This not only provides a better sense of scale and connectability, but offers light and visibility into the first floor shared spaces.”
The all precast concrete design also enabled larger spans so the parking area could be sandwiched into the interior of the building, leaving room for welcoming external spaces along the building’s edges, says Auggy Chung regional business development manager for Spancrete, the precaster on the project. He notes that designing the structure to handle the transition from the parking to the living space was a challenge. “We needed the design to incorporate significant transfer loads resulting in a unique precast design.”
Though Chung says that his favorite part of the project was how the precast concrete design delivered an enticing look and feel while still utilizing the durability and function of precast. “The architectural features in the end resemble jigsaw puzzle pieces, making it a very interesting, durable, and unique addition to the local community.”