The Sanford Heart Hospital in Sioux Falls, S.Dak., looks more like a castle than a medical building. The 213,000 ft2 (19,800 m2) hospital features a soaring clock tower, breezy open entryways, a detailed thin brick facade, and rich coloring that reflects the institution's signature collegiate gothic style. The gothic look was achieved quickly and cost-effectively through the use of a high-performance precast concrete facade, says Tom Kelley, president of Gage Brothers.
Precast concrete wasn't part of the original design. Initially, the owners envisioned a conventional full-brick job with steel stud backup, but it just wasn't practical. The time and cost to scaffold and brick the massive structure were untenable and would have caused unacceptable disruption, Kelley says. "It was a very tight site on a large host campus, so site disturbance and lack of room for a masonry crew did not make sense."
Instead, Gage suggested thin-brick-clad precast concrete panels. Precast concrete not only solved the site problem but cut months from the site work, saving more than $1 million, Kelley says.
Precast concrete provided a higher-performance material to deliver better humidity management for the hospital. "With all the precast banding throughout the brick field, the moisture control would have seen a major challenge with a conventional system," Kelley says. "Integrally casting all the banding within the precast panel system solved this problem."
One of the most unique features of the building design is the elaborate clock tower that anchors one corner of the hospital. The designers were initially concerned about the need for a backup steel system to support the multisided design of the columns, which is common in a conventional cavity wall system. But the self-supporting spanning nature of precast concrete eliminated that problem, Kelley says. "By utilizing precast, the project was able to save tons of steel that would have been required with a conventional brick and stud system."
Gage added further material savings with a unique clamshell design for the upper-level windows that extend 4 ft (1.2 m) beyond the structure. Instead of building three framing sections to hold the roof, sides, and floor of the windows, Gage casts them entirely in precast concrete, eliminating the need for framing altogether. "That was a fun and unique solution for this project," Kelley says.
They also created an all-precast concrete solution for the four-sided columns of the porte-cochère where patients are dropped off. "The porte-cochère thin brick panel system provided a durable solution with both inside and outside faces being precast," he says.
The owners are very happy with the way the design turned out, and they look forward to the reduced maintenance costs of the precast concrete facade.
"A conventional brick system with 2500 psi (17 MPa) mortar joints would need tuck-pointing every 20 years," Kelley says, "but you never have to tuck-point thin-brick-clad precast panels."