Let There Be Light, but Not Too Much
Syska Brings Shade and Comfort to Christ Cathedral
Christ Cathedral, a 78,000-square-foot, all-glass structure designed by famed architect Phillip Johnson, is undeniably striking. Until recently, however, it was also undeniably uncomfortable, thanks to solar glare and a lack of air conditioning. Change came with a $72.3-million renovation, launched in February of 2017 and completed in July of 2019. As part of the renovation’s project team, Syska designed systems that significantly increased the comfort levels for worshippers, visitors, and staff alike.
The building, which was originally completed in 1981, is one of the most recognizable landmarks in Orange County, California. Televangelist Robert Schuller hosted the popular “Hour of Power” program on the site, which was then known as Crystal Cathedral. In 2013, the Roman Catholic Diocese of Orange purchased and renamed the cathedral and the surrounding campus. Since the acquisition, the Diocese “has worked tirelessly to ensure the property’s history and integrity while undertaking major renovations and improvements,” according to the publication Becoming Christ Cathedral: A Story of Faith and Transformation.
Syska’s role in the cathedral renovation encompassed MEP engineering, security, fire alarm design, low-voltage engineering, and high-performance building analysis. Other members of the project team included Johnson Fain (architect), David Partners (owner’s representative), Snyder Langston (general contractor), Nabih Youssef & Associates (structural engineer), TAIT & Associates (civil engineer), Idibri (acoustics and AV), Francis Krahe & Associates (lighting design), and Rios Clementi Hale Studios (landscape design).
Syska’s role in the cathedral renovation encompassed MEP engineering, security, fire alarm design, low-voltage engineering, and high-performance building analysis.
In upgrading systems, Syska had to address several significant challenges. One, as mentioned earlier, was the indoor temperature. Rob Bolin, senior principal, describes the problem: “If you combine the Southern California climate with an all-glass building, high occupancy, and heat from broadcasting equipment, and you lack mechanical cooling, it’s nearly impossible to attain thermal comfort for much of the year. You also have to factor in global warming, which has led to rising temperatures in recent years. We had some hard work ahead of us.”
You also have to factor in global warming, which has led to rising temperatures in recent years. We had some hard work ahead of us.
To determine the best ways to optimize thermal comfort, Syska conducted energy modeling, computational fluid dynamics (CFD) modeling, and daylighting design analysis. But thermal comfort was only one part of the equation: Syska had to meet strict acoustic requirements that supported not only the quality of broadcasts, but also the sound of the refurbished Hazel Wright Organ. With 16,000 metal and wooden pipes, the organ is the world’s fourth-largest pipe organ in a church environment.
Eventually, the team decided that a quatrefoil shading system would enhance both the thermal comfort and the acoustics. Quatrefoils are triangular metal sails that are cut into four pieces, each of which is moveable and tunable manually and positioned throughout the inside of the cathedral. The adjustable “petals” of each quatrefoil can be open or closed according to their solar orientation, thus reducing daytime glare, modulating natural light, and displaying rich translucent patterns during both daytime and nighttime. The positioning of the petals also dampens or increases volume as needed.
Issues of comfort and sound also emerged in the HVAC design. “We had to maintain certain levels of humidity for the organ, but we had to balance those with suitable levels of air conditioning,” Rob recalls. “To figure out a way to accomplish both objectives, we worked closely with the acoustic engineer and an organ specialist.”
To complicate matters further, Syska faced two additional obstacles: limited space for mechanical equipment and the requirement to maintain the architectural integrity of the cathedral. These necessitated a system with invisible ductwork and air devices. Fortunately, the decrease in solar gain through the quatrefoils made it possible to design a smaller mechanical cooling system. Based on all of these considerations, Syska designed a hybrid semi-mixed supply-air system that cools supply air near low levels, allows heat to stratify and rise up with the air, brings airborne contaminants up and away from people, and releases the contaminants through motorized louvers.
We had to maintain certain levels of humidity for the organ, but we had to balance those with suitable levels of air conditioning.
Rob found the design process, despite its complexities, extremely satisfying. As he explains: “We were able to modernize an architecturally significant building while protecting the health and well-being of people using it. That was a big driver for me and my team.”
He reports that the Diocese and parishioners are thrilled with the results. The engineering community has also responded with enthusiasm: Engineering News-Record recently named the renovation the 2020 Best Project for Southern California in the Cultural/Worship category.
Rob notes that Syska has been involved in renovations on the campus for nearly two decades. “Each time we take on a new project, we focus on preserving key architectural elements while overhauling and future-proofing systems,” he says. “That’s the recipe for an iconic structure that endures.”
Each time we take on a new project, we focus on preserving key architectural elements while overhauling and future-proofing systems. That’s the recipe for an iconic structure that endures.
Photography © 2020 Tom Bonner