While most solid wood projects are hybrids, with a steel or concrete siding system, Cincinnati Public Radio’s (CPR) new $32 million headquarters in Evanston is something of an anomaly.
The lateral system of the 35,000 square meter structure is composed of cross-laminated timber (CLT) shear walls, creating a building with a superstructure almost entirely composed of solid timber, explains Dean Lewis, director of solid timber and prefabrication at Skanska , the project project. construction manager
“The entire pillar and beam structure, second floor, roof structure and a selection of interior shear walls and exterior perimeter walls are made from solid wood,” he says.
When completed in early 2025, CPR’s new home for 88.5 WMUB, 90.9 WGUC and 91.7 WVXU will be the first two-story solid wood building in both Cincinnati and the Midwest region .
Almost the entire project is made of solid wood, including some of the interior shear walls and exterior perimeter walls.
Photo courtesy of Skanska
In addition to serving as a sustainable resource, solid wood also leaned toward the owner’s desire for an iconic building that was recognizable, welcoming, and adaptable. However, given the differences of a solid wood system from typical concrete or steel options, the design team worked carefully to find the optimal structural bay, says Adam Luginbill, senior project architect at emersion DESIGN . This allowed the team to maximize the potential of the CLT panels and keep them to a reasonable thickness while minimizing both the size and amount of beams required.
Delivered under a CMAR contract with GMP, the 35,000 square meter facility features two on-air studios, two more for interviews and one for performances, along with 11,000 square meters of office space. A free-to-use podcast booth will allow anyone in the community to record their own content, while outdoor meeting and performance areas will offer a variety of programming, including concerts, educational programs and receptions.
Planning began in 2018, with emersion DESIGN and Skanska already on board, but the COVID-19 pandemic hampered CPR’s fundraising efforts.
“As a non-profit organization, CPR had to have the funds to build the building, which is the largest project in the history of its stations,” explains Richard Eiswerth, CPR President, CEO and CEO. This effort also marks the first traditional capital campaign in CPR’s more than 60-year history.
Although the owner considered more than two dozen sites and the possibilities of building or renovating an existing space, the station settled on a location in Evanston’s diverse and growing neighborhood where CPR can invest and give back, Eiswerth says .
The site, which was once a parking lot, also borders Evanston Park, a public space where the station plans to host concerts and other events.
“The building is meant to feel integrated and complement this public space,” says Nikki Goldstein, design architect at emersion DESIGN. “Visually, it is a simple pavilion with transparent outer walls. But constructing a seemingly simple building is often a complex endeavor. The execution of glass walls and exposed structure is critical to its success: there is no place to hide imperfections in a simple structure.”
To safeguard the interior solid wood elements, temporary protection was installed on all columns from the slab to 8 feet above the floor.
Photo courtesy of Skanska
fast rise
Since construction began in September 2023, work has progressed rapidly. Construction of the building began in November and after just 34 working days, Skanska crews installed the 498 panels comprising the shear walls, wall and floor panels, columns, beams and ceiling panels; the final roof panel was installed on December 22.
As the massive timber arrives ready to assemble, delivered with the help of 28 trucks, extensive coordination was vital before fabrication began. Early engagement and a partnership with mass timber manufacturer Nordic Structures also helped ensure the CPR project had a production timeline that aligned with its schedule, explains Jeff Smoker, Skanska’s project manager.
“As a non-profit entity, CPR had to have the funds to build the building, which is the largest project in the history of its stations.”
—Richard Eiswerth, president, CEO and CEO of Cincinnati Public Radio
From there, BIM coordination served as a critical tool to ensure that both the timber erection and system installation went smoothly.
Although the structure has reached the top, much of the building’s interior solid wood elements remain exposed, so preserving these structures while work progresses has proven challenging.
“Skanska rushed to install the roof and bought a complete RWES [reusable weather enclosure system] for the exterior of the building in an effort to minimize the impact of moisture on the finished product,” says Dustin Hopkins, Skanska superintendent. “The construction team had to do a lot of things differently than due to the finished timber. Tasks such as lay-out and material cutting stations had to be well coordinated so that the timber was protected. Temporary protection was also installed on all columns from slab to 8 feet off the ground
As an alternative to a traditional reinforced plastic wall system that would be thrown away at the end of a project, the RWES “installs faster, performs better in high winds and rain, and can be folded up and shipped to the next project “, he said. he says “The product can also be cut to custom sizes for pitched roof applications such as CPR or to be sequenced with exterior skin and curtain wall installation.”
Although it will appear as a simple pavilion with transparent exterior walls, Cincinnati Public Radio’s headquarters will feature recording facilities housed within an environmentally friendly building.
Rendering courtesy of emersion DESIGN
Sound and Sustainable
Balancing the function of the building with an iconic design has been another challenge. It would have been “quite easy to do the acoustic aspects as they are and lose the aesthetic of what the building could be,” notes Hopkins. “But we were able to make the final building aesthetically pleasing while meeting the acoustic requirements that a studio needs.”
The facility’s studios were designed with solid CLT walls, and each is acoustically insulated with a box-within-a-box design. Meanwhile, the floors feature a structural slab topped by a floating acoustic slab. Neither the framed walls nor the ceilings touch the structure of the building and all penetrations were also sealed.
“Where there are windows, in addition to the exterior glass, there is a 1-inch-thick layer of laminated glass on the decoupled interior wall,” Luginbill says.
During design, acoustic architecture consultant WSDG recorded the site’s traffic noise to simulate how it would sound in both the studios and the boardroom that would sit next to the road, he says.
“Radiant heating and cooling meant that ductwork could be largely eliminated from areas with exposed structure.”
—Adam Luginbill, Senior Project Architect, emersion DESIGN
Sustainability and occupant health were also owner-initiated priorities, with a LEED Gold goal established early in the design process.
“In addition to specifying low-emission materials, there will be indoor air quality testing at the end of construction. The use of natural materials, mainly exposed solid wood, and natural lighting are aimed improve the well-being of the occupants,” says Luginbill.
In accordance with a design that aims to highlight the very structure of the building, the grid of columns is exposed. But wherever there are partitions, they are pulled back from the columns so the structure is visible, Goldstein says. The stairs were also strategically placed to show off the CLT shear walls. Enclosed spaces were moved away from the glass on the second floor, creating an open office environment.
However, integrating building systems within such a limited enclosed space required careful management and some creativity.
“The design team concentrated the ducts, plumbing and cable trays in the core of the building so that the areas around the perimeter, with the exposed structure, were as free of visual obstruction as possible,” says Luginbill, adding that any system within exposed areas. they kept as discreet as possible.
But these constraints were also inspiring, as was the building’s HVAC system, which uses radiant heating and cooling, suggested by MEP engineer CMTA.
“Since the program called for acoustic control, the design team recognized that this would mean a tightly sealed envelope and that moisture inside the building could be tightly controlled,” adds Luginbill. “Radiant heating and cooling meant that ductwork could be largely eliminated from exposed structural areas, and its energy efficiency contributed to sustainability goals.”
In fact, the only ducts anywhere in the building are solely for outside air supply and exhaust, which is hidden in the core of the building. This system also eliminates recirculation air, helping to improve air quality for occupants, who will be able to take advantage of the facility’s recording spaces and outreach programs once the building is complete next year .
Meanwhile, crews are nearing the halfway mark of the project in mid-March, having logged 17,500 business hours with zero recordables.
