One of the biggest design and manufacturing challenges of the parking structure’s architectural precast concrete panels was to blend with the campus architecture using a complementary material palette and patterned façade that resembles the fenestrations on existing campus structures. Photo: Ratio. PRECAST CONCRETE HELPS PARKING STRUCTURE GAIN HONORS Duke University has been committed to sustainable building standards since 1993, and its construction of a new parking structure in 2010 did not deviate from that commitment. Clad in architectural precast concrete, the Research Drive Parking Garage not only achieved LEED certification but also demonstrated a wide array of design and construction benefits of precast concrete: • Fast construction timeline • Reduced construction activity on an already tight building site • Reduced carbon footprint • Ease of architectural integration with existing campus structures • Long-term, low-maintenance durability The façade features a warm melding of colors and textures, including a smooth monolithic finish made with a red stone ag-gregate that complements the locally quarried Duke stone used in the façade. The neutral color of the precast concrete also con-tributes to a reduced heat-island effect. “The campus has some topography to it, so the site itself was multilevel,” says Milliken. That meant vehicles could enter the parking structure at two different levels. An exterior express ramp on one side of the structure allowed all the floor plates to be flat, providing passive security with unobstructed internal views. The structure also features a high level of service lighting along with painting of the undersides of the concrete structure to provide maximum visibility. Parking Structure Makes the Grade The use of regional materials, including precast concrete compo-nents manufactured only 25 miles away from the jobsite, contrib-uted to a low carbon footprint during construction and helped add LEED points for the project. Also contributing to the project’s LEED certification were site credits for removal of surface parking lots, the structure’s con-nectivity to mass transit, use of recycled steel in the structural frame, reforestation of 75% of the building site with native plants and trees, and a roof outfitted with photovoltaics to provide power to the parking structure and other campus structures. Precast concrete wasn’t the only locally sourced material. The Duke stone used to accent the parking structure tours was quar-ried locally. “It became a garage of multiple materials that really complemented each other,” Lohman says. “We liked that it was durable. All you may have to ever do is clean it.” “We kicked the door open on getting this garage LEED certi-fied,” he adds. “We insulated support spaces and met energy codes that were new. We were one of the first to incorporate LED lighting.” Lohman says Duke University wanted a high-quality structure that was architecturally attractive. “That’s easier to achieve with precast concrete,” he says. “Hopefully this garage will be timeless for how it serves users, how it looks, and its sustainable features. It’s an iconic project for buildings of this type.” A major benefit of using precast concrete is its long-term du-rability. “With proper maintenance, this structure will be usable for 50 years and beyond,” says Travis Fox, vice president of sales for GATE Precast, the precast concrete producer for the project. In July 2024, GATE Precast joined Wells, expanding the national footprint. One of the biggest design and manufacturing challenges of the structure’s architectural precast concrete panels was to blend with the campus architecture using a complementary material palette and patterned façade that resembles the fenestrations on existing campus structures. This required detailing of the deep precast concrete column cover returns as well as reveals and exterior panels at the edge of the roof trellis planter boxes. The depth of the precast concrete covers that hide the building’s con-crete structural columns gives the exterior a sculptural appear-ance. Precast concrete panels and column covers also provide a “punched opening” rhythm to further complement the designs of adjacent university structures.
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