A May-December romance is drawing cheers from Salt Lake City residents. Salt Lake City's historic Capitol Theatre celebrated its centennial in 2014 with some cosmetic touch-ups, but then also emerged with a new companion next door: the Jesse Eccles Quinney Ballet Centre. The newcomer is infusing energy into downtown and breathing life into the historic theater, though the structural balance of pairing the old and new "performers" had engineers keeping a close eye on the choreography.

Image courtesy of HKS Inc. - Jack E. Madsen III
The ballet center provides Utah's Ballet West with larger rehearsal space and a headquarters next door to its performance home in the Capitol Theatre.
Image courtesy of HKS Inc. - Jack E. Madsen III
Construction of the ballet center coincided with the first stage of renovations to the century-old theater, including refurbishing the seating area.

The 55,000-sq-ft, $22-million ballet center incorporates thematic elements from the old theater along with more contemporary designs. It is connected and integrated with the old theater by a full-height glass atrium on the theater's west wall. The center's angled, 150-ft-long facade nearly mirrors the envelope of the adjacent Capitol Theatre.

The Utah Performing Arts Center in Salt Lake City also is under construction and scheduled for opening in more than a year (ENR Mountain States 6/16/14 p. MS49). It will host some of the large-scale Broadway-style performances now held at the Capitol Theatre. Seating in the old theater will be reduced from the current 1,876 to 1,550 to create a more intimate space and improve sightlines.

Salt Lake City-based Okland Construction wrapped up construction of the ballet center just in time for the 2014 holiday season.

To construct the ballet center and attach it to its historic partner—without compromising either building—engineers had to first complete a comprehensive structural study of the historic theater, says structural engineer Mark Harris, a principal at Salt Lake City-based Reaveley Engineers + Associates.

"Prior to the design work, we did a feasibility study to see if we could make the openings we wanted in the west wall of the Capitol Theatre. We are dealing with a building that is 100-year-old unreinforced masonry," says Harris.

"The county couldn't afford a structural upgrade of the Capitol [Theatre], so we had to see how we could make the penetrations but keep the buildings physically independent," Harris adds.

The number of wall penetrations was limited to 12, with the largest on the main floor for the lobby expansion. Workers reinforced the west wall of the theater with a 6-in. to 8-in. shotcrete overlay. The steel frames of the new openings were attached to the existing brick and incorporated with shotcrete along the entire wall.

"With the amount of openings and the reinforcement we did, we didn't increase the force on the existing building more than 10%, which was the limit we determined it could withstand," Harris says.

More structural challenges emerged in constructing the large, open dance rehearsal spaces on the upper floors, the largest at 48 ft by 80 ft. To allow for daylight and views, designers wanted large expanses of glass for the studios' west walls. Performers also wanted unobstructed space inside.

Harris says the engineers considered diagonal braces on the west wall but they would have obstructed the windows. "We also had substantial glass above and below on the floors, and so that exterior was unavailable for us to do anything with," he says.

Moment Connections

The project team turned to SidePlate, a Mission Viejo, Calif.-based company known for its patented design of reinforced moment-frame connections.

SidePlate makes "very robust connections, and we could reduce the size of the beams and columns we did use," says Harris. "Because we could reduce the steel in some areas, it lowered the cost and covered the licensing fees from SidePlate. The other advantage was it was a quick solution."